<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019fee81-6e3f-72bf-a2d5-b05d2ddf90ee,g:3b4103ee-ec1b-4e52-a54f-8c8c6bc09d18-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="https://xbrl.org/2023/arcrole/summation-item" xlink:type="simple" xlink:href="https://www.xbrl.org/2023/calculation-1.1.xsd#summation-item"/>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/CondensedConsolidatedStatementsofIncomeLoss" xlink:type="simple" xlink:href="cnr-20260930.xsd#CondensedConsolidatedStatementsofIncomeLoss"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/CondensedConsolidatedStatementsofIncomeLoss" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostsAndExpenses_019fee81-6f98-70ae-9d28-e7d563be3bd0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostsAndExpenses"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_019fee81-6f98-70fb-bc74-72322e4d268b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CostsAndExpenses_019fee81-6f98-70ae-9d28-e7d563be3bd0" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_019fee81-6f98-70fb-bc74-72322e4d268b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAndAmortization_019fee81-6f98-7376-bcac-7ed9a2a55af8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationAndAmortization"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CostsAndExpenses_019fee81-6f98-70ae-9d28-e7d563be3bd0" xlink:to="loc_us-gaap_DepreciationAndAmortization_019fee81-6f98-7376-bcac-7ed9a2a55af8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherOperatingIncomeExpenseNet_019fee81-6f98-717a-8b6b-bf3fbe2087ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherOperatingIncomeExpenseNet"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CostsAndExpenses_019fee81-6f98-70ae-9d28-e7d563be3bd0" xlink:to="loc_us-gaap_OtherOperatingIncomeExpenseNet_019fee81-6f98-717a-8b6b-bf3fbe2087ff" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization_019fee81-6f98-7180-9cb1-8f5de0ec954f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CostsAndExpenses_019fee81-6f98-70ae-9d28-e7d563be3bd0" xlink:to="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization_019fee81-6f98-7180-9cb1-8f5de0ec954f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_019fee81-6f98-7b5d-a8b1-8fe6fa0ab406" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019fee81-6f98-7a73-9fd3-d88d589d45d2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019fee81-6f98-7b5d-a8b1-8fe6fa0ab406" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019fee81-6f98-7a73-9fd3-d88d589d45d2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostsAndExpenses_019fee81-6f98-7e18-977e-411b989d2def" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostsAndExpenses"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019fee81-6f98-7b5d-a8b1-8fe6fa0ab406" xlink:to="loc_us-gaap_CostsAndExpenses_019fee81-6f98-7e18-977e-411b989d2def" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019fee81-6f98-7135-bb7a-df8e3ccbb227" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019fee81-6f98-7b64-a2fe-e70ab3a5eb43" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_019fee81-6f98-7135-bb7a-df8e3ccbb227" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019fee81-6f98-7b64-a2fe-e70ab3a5eb43" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-6f98-7c51-ab41-5b6a2d890631" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_019fee81-6f98-7135-bb7a-df8e3ccbb227" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-6f98-7c51-ab41-5b6a2d890631" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-6f98-7f16-ae51-d7aa659c2046" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_019fee81-6f98-7a80-95fd-6fa830487eee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-6f98-7f16-ae51-d7aa659c2046" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_019fee81-6f98-7a80-95fd-6fa830487eee" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeInterest_019fee81-6f98-7a5c-b4b3-f75368272296" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIncomeInterest"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-6f98-7f16-ae51-d7aa659c2046" xlink:to="loc_us-gaap_InvestmentIncomeInterest_019fee81-6f98-7a5c-b4b3-f75368272296" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_019fee81-6f98-750e-bbc6-3fc1b7197d7b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-6f98-7f16-ae51-d7aa659c2046" xlink:to="loc_us-gaap_OperatingIncomeLoss_019fee81-6f98-750e-bbc6-3fc1b7197d7b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PensionAndOtherPostretirementBenefitExpense_019fee81-6f98-70ea-a7c9-33a75a23d2ca" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PensionAndOtherPostretirementBenefitExpense"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-6f98-7f16-ae51-d7aa659c2046" xlink:to="loc_us-gaap_PensionAndOtherPostretirementBenefitExpense_019fee81-6f98-70ea-a7c9-33a75a23d2ca" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_019fee81-6f98-7fe0-b5cb-d7629fa6418f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-6f98-7f16-ae51-d7aa659c2046" xlink:to="loc_us-gaap_InterestExpenseNonoperating_019fee81-6f98-7fe0-b5cb-d7629fa6418f" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/CondensedConsolidatedStatementsofComprehensiveIncomeLoss" xlink:type="simple" xlink:href="cnr-20260930.xsd#CondensedConsolidatedStatementsofComprehensiveIncomeLoss"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/CondensedConsolidatedStatementsofComprehensiveIncomeLoss" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019fee81-6f98-7c06-ab02-a61602a042e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_019fee81-6f98-7178-8b85-911169e645c5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019fee81-6f98-7c06-ab02-a61602a042e2" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_019fee81-6f98-7178-8b85-911169e645c5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_019fee81-6f98-7a31-8248-3537f5159d95" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019fee81-6f98-7c06-ab02-a61602a042e2" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_019fee81-6f98-7a31-8248-3537f5159d95" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_019fee81-6f98-7ffd-9001-e472bf68b34b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019fee81-6f98-7c88-89e3-0f64fc065307" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_019fee81-6f98-7ffd-9001-e472bf68b34b" xlink:to="loc_us-gaap_NetIncomeLoss_019fee81-6f98-7c88-89e3-0f64fc065307" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019fee81-6f98-754e-82bc-86317f041ca6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_019fee81-6f98-7ffd-9001-e472bf68b34b" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019fee81-6f98-754e-82bc-86317f041ca6" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/CondensedConsolidatedBalanceSheets" xlink:type="simple" xlink:href="cnr-20260930.xsd#CondensedConsolidatedBalanceSheets"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/CondensedConsolidatedBalanceSheets" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_019fee81-6f98-7090-bbda-3663470f70c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsNoncurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent_019fee81-6f98-7388-9ba9-49d6372e6853" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherAssetsNoncurrent_019fee81-6f98-7090-bbda-3663470f70c9" xlink:to="loc_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent_019fee81-6f98-7388-9ba9-49d6372e6853" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsMiscellaneousNoncurrent_019fee81-6f98-71b0-84fd-ceabf8128c2d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsMiscellaneousNoncurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherAssetsNoncurrent_019fee81-6f98-7090-bbda-3663470f70c9" xlink:to="loc_us-gaap_OtherAssetsMiscellaneousNoncurrent_019fee81-6f98-71b0-84fd-ceabf8128c2d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_FundsForAssetRetirementObligations_019fee81-6f98-7d52-a5b1-46bbc79696d5" xlink:href="cnr-20260930.xsd#cnr_FundsForAssetRetirementObligations"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherAssetsNoncurrent_019fee81-6f98-7090-bbda-3663470f70c9" xlink:to="loc_cnr_FundsForAssetRetirementObligations_019fee81-6f98-7d52-a5b1-46bbc79696d5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_019fee81-6f98-7f35-a3ce-31857b65acf1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableCurrent_019fee81-6f98-72af-ad93-aa9d3719276f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019fee81-6f98-7f35-a3ce-31857b65acf1" xlink:to="loc_us-gaap_AccountsPayableCurrent_019fee81-6f98-72af-ad93-aa9d3719276f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_019fee81-6f98-7191-910c-4519b701500f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019fee81-6f98-7f35-a3ce-31857b65acf1" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_019fee81-6f98-7191-910c-4519b701500f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_019fee81-6f98-7aad-ad29-d3bbc3dd4db1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019fee81-6f98-7f35-a3ce-31857b65acf1" xlink:to="loc_us-gaap_AccruedLiabilitiesCurrent_019fee81-6f98-7aad-ad29-d3bbc3dd4db1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesNoncurrent_019fee81-6f98-7490-8d07-90176c496af2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesNoncurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_019fee81-6f98-7943-8abe-1810372642ca" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligations"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesNoncurrent_019fee81-6f98-7490-8d07-90176c496af2" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_019fee81-6f98-7943-8abe-1810372642ca" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent_019fee81-6f98-7ba5-abb9-7078fe21d3a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesNoncurrent_019fee81-6f98-7490-8d07-90176c496af2" xlink:to="loc_us-gaap_OtherPostretirementDefinedBenefitPlanLiabilitiesNoncurrent_019fee81-6f98-7ba5-abb9-7078fe21d3a7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_EmployeeRelatedLiabilitiesMedicalAndDisabilityBenefitsNoncurrent_019fee81-6f98-70f4-9af8-89cff03072a0" xlink:href="cnr-20260930.xsd#cnr_EmployeeRelatedLiabilitiesMedicalAndDisabilityBenefitsNoncurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesNoncurrent_019fee81-6f98-7490-8d07-90176c496af2" xlink:to="loc_cnr_EmployeeRelatedLiabilitiesMedicalAndDisabilityBenefitsNoncurrent_019fee81-6f98-70f4-9af8-89cff03072a0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetRetirementObligationsNoncurrent_019fee81-6f98-7f1d-9d54-4a338b6ca9f3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetRetirementObligationsNoncurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesNoncurrent_019fee81-6f98-7490-8d07-90176c496af2" xlink:to="loc_us-gaap_AssetRetirementObligationsNoncurrent_019fee81-6f98-7f1d-9d54-4a338b6ca9f3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WorkersCompensationLiabilityNoncurrent_019fee81-6f98-7240-a5e8-4a3c42fd25a3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WorkersCompensationLiabilityNoncurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesNoncurrent_019fee81-6f98-7490-8d07-90176c496af2" xlink:to="loc_us-gaap_WorkersCompensationLiabilityNoncurrent_019fee81-6f98-7240-a5e8-4a3c42fd25a3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPensionPlanLiabilitiesNoncurrent_019fee81-6f98-73bc-8461-abf14d3afea1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPensionPlanLiabilitiesNoncurrent"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesNoncurrent_019fee81-6f98-7490-8d07-90176c496af2" xlink:to="loc_us-gaap_DefinedBenefitPensionPlanLiabilitiesNoncurrent_019fee81-6f98-73bc-8461-abf14d3afea1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxLiabilitiesNet_019fee81-6f98-720e-a434-08996e3893cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxLiabilitiesNet"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesNoncurrent_019fee81-6f98-7490-8d07-90176c496af2" xlink:to="loc_us-gaap_DeferredIncomeTaxLiabilitiesNet_019fee81-6f98-720e-a434-08996e3893cd" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_019fee81-6f98-7f61-8f3c-9e584f0ca220" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesNoncurrent"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesNoncurrent_019fee81-6f98-7490-8d07-90176c496af2" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_019fee81-6f98-7f61-8f3c-9e584f0ca220" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019fee81-6f98-7a6c-be35-42a1b323afeb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_019fee81-6f98-7600-94dd-0c1b9a181181" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019fee81-6f98-7a6c-be35-42a1b323afeb" xlink:to="loc_us-gaap_AssetsCurrent_019fee81-6f98-7600-94dd-0c1b9a181181" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_019fee81-6f98-7983-ae90-da2421e2ad77" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsNoncurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019fee81-6f98-7a6c-be35-42a1b323afeb" xlink:to="loc_us-gaap_OtherAssetsNoncurrent_019fee81-6f98-7983-ae90-da2421e2ad77" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_019fee81-6f98-724d-afb1-7c984fcc42c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019fee81-6f98-7a6c-be35-42a1b323afeb" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_019fee81-6f98-724d-afb1-7c984fcc42c6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019fee81-6f98-7c24-ade9-25687cfd4163" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesNoncurrent_019fee81-6f98-7f02-b239-6857ce57d797" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesNoncurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019fee81-6f98-7c24-ade9-25687cfd4163" xlink:to="loc_us-gaap_LiabilitiesNoncurrent_019fee81-6f98-7f02-b239-6857ce57d797" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_019fee81-6f98-756b-b570-e24ae898d1d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019fee81-6f98-7c24-ade9-25687cfd4163" xlink:to="loc_us-gaap_LiabilitiesCurrent_019fee81-6f98-756b-b570-e24ae898d1d8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_019fee81-6f98-7289-83f0-d468e210c835" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019fee81-6f98-7f3e-b049-f34dc7e5f78d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019fee81-6f98-7289-83f0-d468e210c835" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019fee81-6f98-7f3e-b049-f34dc7e5f78d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_019fee81-6f98-7f66-984f-eb3426841b82" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019fee81-6f98-7289-83f0-d468e210c835" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_019fee81-6f98-7f66-984f-eb3426841b82" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherReceivablesNetCurrent_019fee81-6f98-706f-bd72-f250758c9efd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherReceivablesNetCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019fee81-6f98-7289-83f0-d468e210c835" xlink:to="loc_us-gaap_OtherReceivablesNetCurrent_019fee81-6f98-706f-bd72-f250758c9efd" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_019fee81-6f98-7174-a057-2d6e4d0d6c59" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryNet"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019fee81-6f98-7289-83f0-d468e210c835" xlink:to="loc_us-gaap_InventoryNet_019fee81-6f98-7174-a057-2d6e4d0d6c59" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsCurrent_019fee81-6f98-7077-83e4-9d9af26f0ccb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsCurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019fee81-6f98-7289-83f0-d468e210c835" xlink:to="loc_us-gaap_OtherAssetsCurrent_019fee81-6f98-7077-83e4-9d9af26f0ccb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_019fee81-6f98-7679-96a0-6366356903c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019fee81-6f98-7336-8914-c0540a7a2511" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019fee81-6f98-7679-96a0-6366356903c6" xlink:to="loc_us-gaap_Liabilities_019fee81-6f98-7336-8914-c0540a7a2511" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsAndContingencies_019fee81-6f98-708d-8154-b18a4effb857" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommitmentsAndContingencies"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019fee81-6f98-7679-96a0-6366356903c6" xlink:to="loc_us-gaap_CommitmentsAndContingencies_019fee81-6f98-708d-8154-b18a4effb857" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019fee81-6f98-7b29-a1f9-dcf68c1ca4e3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019fee81-6f98-7679-96a0-6366356903c6" xlink:to="loc_us-gaap_StockholdersEquity_019fee81-6f98-7b29-a1f9-dcf68c1ca4e3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019fee81-6f98-71c0-869c-b4f8d12828a2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapital_019fee81-6f98-7fb3-8d01-087d4514bd33" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapital"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019fee81-6f98-71c0-869c-b4f8d12828a2" xlink:to="loc_us-gaap_AdditionalPaidInCapital_019fee81-6f98-7fb3-8d01-087d4514bd33" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_019fee81-6f98-7094-9208-9c91ac1531a2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019fee81-6f98-71c0-869c-b4f8d12828a2" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_019fee81-6f98-7094-9208-9c91ac1531a2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_019fee81-6f98-7810-ab42-7761c88b07c7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019fee81-6f98-71c0-869c-b4f8d12828a2" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_019fee81-6f98-7810-ab42-7761c88b07c7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValue_019fee81-6f98-740d-86ee-3bd5ee7ec71f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockValue"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019fee81-6f98-71c0-869c-b4f8d12828a2" xlink:to="loc_us-gaap_CommonStockValue_019fee81-6f98-740d-86ee-3bd5ee7ec71f" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/CondensedConsolidatedStatementsofStockholdersEquity" xlink:type="simple" xlink:href="cnr-20260930.xsd#CondensedConsolidatedStatementsofStockholdersEquity"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/CondensedConsolidatedStatementsofStockholdersEquity" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_019fee81-6f98-79a6-bcf8-ba42c4f585e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019fee81-6f98-785d-a800-23aecd3aa56b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_019fee81-6f98-79a6-bcf8-ba42c4f585e6" xlink:to="loc_us-gaap_NetIncomeLoss_019fee81-6f98-785d-a800-23aecd3aa56b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_019fee81-6f98-72e0-aeb4-1703661af10b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_019fee81-6f98-79a6-bcf8-ba42c4f585e6" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_019fee81-6f98-72e0-aeb4-1703661af10b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_019fee81-6f98-72fd-942c-8aea1b6848ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_019fee81-6f98-79a6-bcf8-ba42c4f585e6" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_019fee81-6f98-72fd-942c-8aea1b6848ee" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/CondensedConsolidatedStatementsofCashFlows" xlink:type="simple" xlink:href="cnr-20260930.xsd#CondensedConsolidatedStatementsofCashFlows"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/CondensedConsolidatedStatementsofCashFlows" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fee81-6f98-79d2-ab4b-559d604bb089" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeasePrincipalPayments_019fee81-6f98-7511-aa70-944863cafae3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeasePrincipalPayments"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fee81-6f98-79d2-ab4b-559d604bb089" xlink:to="loc_us-gaap_FinanceLeasePrincipalPayments_019fee81-6f98-7511-aa70-944863cafae3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt_019fee81-6f98-7cfc-aecc-10e06d6b8c2b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIssuanceOfLongTermDebt"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fee81-6f98-79d2-ab4b-559d604bb089" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt_019fee81-6f98-7cfc-aecc-10e06d6b8c2b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfOtherDebt_019fee81-6f98-7350-9cd0-f0b2c6299265" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfOtherDebt"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fee81-6f98-79d2-ab4b-559d604bb089" xlink:to="loc_us-gaap_RepaymentsOfOtherDebt_019fee81-6f98-7350-9cd0-f0b2c6299265" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_019fee81-6f98-7e2f-90ad-8e56ea43b642" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fee81-6f98-79d2-ab4b-559d604bb089" xlink:to="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_019fee81-6f98-7e2f-90ad-8e56ea43b642" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_019fee81-6f98-7de4-abf8-fe566c975a00" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fee81-6f98-79d2-ab4b-559d604bb089" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_019fee81-6f98-7de4-abf8-fe566c975a00" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfFinancingCosts_019fee81-6f98-7a9b-b705-e93333d55b05" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsOfFinancingCosts"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fee81-6f98-79d2-ab4b-559d604bb089" xlink:to="loc_us-gaap_PaymentsOfFinancingCosts_019fee81-6f98-7a9b-b705-e93333d55b05" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_PaymentsOfExciseTaxOnShareRepurchases_019fee81-6f98-7270-a3cb-c9c75f2acf8b" xlink:href="cnr-20260930.xsd#cnr_PaymentsOfExciseTaxOnShareRepurchases"/>
    <link:calculationArc order="7" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fee81-6f98-79d2-ab4b-559d604bb089" xlink:to="loc_cnr_PaymentsOfExciseTaxOnShareRepurchases_019fee81-6f98-7270-a3cb-c9c75f2acf8b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDividends_019fee81-6f98-7e82-b2cf-677b3268b906" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsOfDividends"/>
    <link:calculationArc order="8" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fee81-6f98-79d2-ab4b-559d604bb089" xlink:to="loc_us-gaap_PaymentsOfDividends_019fee81-6f98-7e82-b2cf-677b3268b906" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019fee81-6f98-7042-b3d9-c94d70a98bcd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7a22-b5e5-b13d9bdbbbba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019fee81-6f98-7042-b3d9-c94d70a98bcd" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7a22-b5e5-b13d9bdbbbba" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fee81-6f98-71c3-8122-c75422507292" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019fee81-6f98-7042-b3d9-c94d70a98bcd" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019fee81-6f98-71c3-8122-c75422507292" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fee81-6f98-7e41-9c0f-6f49fed39332" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019fee81-6f98-7042-b3d9-c94d70a98bcd" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fee81-6f98-7e41-9c0f-6f49fed39332" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_019fee81-6f98-776e-a604-325027c87ae7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_019fee81-6f98-776e-a604-325027c87ae7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_019fee81-6f98-77a3-ae79-8041949db9b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_019fee81-6f98-77a3-ae79-8041949db9b6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnDispositionOfAssets1_019fee81-6f98-7c03-ab38-fa75ec355190" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnDispositionOfAssets1"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_GainLossOnDispositionOfAssets1_019fee81-6f98-7c03-ab38-fa75ec355190" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_019fee81-6f98-7db8-9316-a9b6f10d5495" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensation"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_ShareBasedCompensation_019fee81-6f98-7db8-9316-a9b6f10d5495" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayable_019fee81-6f98-7ef0-a925-3f890327815a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsPayable"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayable_019fee81-6f98-7ef0-a925-3f890327815a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019fee81-6f98-79d6-b1d6-8c01ecc126a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_NetIncomeLoss_019fee81-6f98-79d6-b1d6-8c01ecc126a1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherCurrentLiabilities_019fee81-6f98-757f-91c1-cd028b16b847" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherCurrentLiabilities"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherCurrentLiabilities_019fee81-6f98-757f-91c1-cd028b16b847" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsAndNotesReceivable_019fee81-6f98-71d6-bd2b-11130cb9ca92" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsAndNotesReceivable"/>
    <link:calculationArc order="8" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsAndNotesReceivable_019fee81-6f98-71d6-bd2b-11130cb9ca92" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInInventories_019fee81-6f98-768b-a2d3-6b3d2046838c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInInventories"/>
    <link:calculationArc order="9" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_IncreaseDecreaseInInventories_019fee81-6f98-768b-a2d3-6b3d2046838c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_019fee81-6f98-7fc4-ba48-0c292f65cae7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherNoncurrentAssets"/>
    <link:calculationArc order="10" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_019fee81-6f98-7fc4-ba48-0c292f65cae7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_019fee81-6f98-7615-96a8-792aba05156e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:calculationArc order="11" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_019fee81-6f98-7615-96a8-792aba05156e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_019fee81-6f98-7ee0-ba7a-78113d3fefd4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit"/>
    <link:calculationArc order="12" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_019fee81-6f98-7ee0-ba7a-78113d3fefd4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNoncashIncomeExpense_019fee81-6f98-7e20-bab7-a5bb14c63197" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNoncashIncomeExpense"/>
    <link:calculationArc order="13" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_OtherNoncashIncomeExpense_019fee81-6f98-7e20-bab7-a5bb14c63197" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherCurrentAssets_019fee81-6f98-7745-bde5-821511bf8b52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherCurrentAssets"/>
    <link:calculationArc order="14" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherCurrentAssets_019fee81-6f98-7745-bde5-821511bf8b52" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAssetRetirementObligations_019fee81-6f98-7f40-b872-91df84b9adea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAssetRetirementObligations"/>
    <link:calculationArc order="15" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_IncreaseDecreaseInAssetRetirementObligations_019fee81-6f98-7f40-b872-91df84b9adea" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019fee81-6f98-7d0b-8d3d-234336d12905" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromEquityMethodInvestments"/>
    <link:calculationArc order="16" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fee81-6f98-7ed4-858e-e97bcdb82aa8" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019fee81-6f98-7d0b-8d3d-234336d12905" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fee81-6f98-7ba5-a825-9b26bec5691e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfShortTermInvestments_019fee81-6f98-7b57-9d5f-0c227a5c068a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromSaleOfShortTermInvestments"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fee81-6f98-7ba5-a825-9b26bec5691e" xlink:to="loc_us-gaap_ProceedsFromSaleOfShortTermInvestments_019fee81-6f98-7b57-9d5f-0c227a5c068a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_019fee81-6f98-7095-ab9e-a0aba7673bdd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForProceedsFromOtherInvestingActivities"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fee81-6f98-7ba5-a825-9b26bec5691e" xlink:to="loc_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_019fee81-6f98-7095-ab9e-a0aba7673bdd" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireShortTermInvestments_019fee81-6f98-7f9d-b06f-177166c59b1e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireShortTermInvestments"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fee81-6f98-7ba5-a825-9b26bec5691e" xlink:to="loc_us-gaap_PaymentsToAcquireShortTermInvestments_019fee81-6f98-7f9d-b06f-177166c59b1e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfProductiveAssets_019fee81-6f98-7d47-9fbb-7becf66d1ab8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromSaleOfProductiveAssets"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fee81-6f98-7ba5-a825-9b26bec5691e" xlink:to="loc_us-gaap_ProceedsFromSaleOfProductiveAssets_019fee81-6f98-7d47-9fbb-7becf66d1ab8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireProjects_019fee81-6f98-7f38-997c-ff68bbdcb2a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireProjects"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fee81-6f98-7ba5-a825-9b26bec5691e" xlink:to="loc_us-gaap_PaymentsToAcquireProjects_019fee81-6f98-7f38-997c-ff68bbdcb2a6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_019fee81-6f98-75eb-911b-d85fd77f4cad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fee81-6f98-7ba5-a825-9b26bec5691e" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_019fee81-6f98-75eb-911b-d85fd77f4cad" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAcquiredFromAcquisition_019fee81-6f98-768a-a1ba-7608eee05e43" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAcquiredFromAcquisition"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fee81-6f98-7ba5-a825-9b26bec5691e" xlink:to="loc_us-gaap_CashAcquiredFromAcquisition_019fee81-6f98-768a-a1ba-7608eee05e43" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireOtherInvestments_019fee81-6f98-7c50-a8fe-4e9e79ca8680" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireOtherInvestments"/>
    <link:calculationArc order="8" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019fee81-6f98-7ba5-a825-9b26bec5691e" xlink:to="loc_us-gaap_PaymentsToAcquireOtherInvestments_019fee81-6f98-7c50-a8fe-4e9e79ca8680" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/BasisofPresentationScheduleofBasicandDilutiveEarningsLossperShareDetails" xlink:type="simple" xlink:href="cnr-20260930.xsd#BasisofPresentationScheduleofBasicandDilutiveEarningsLossperShareDetails"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/BasisofPresentationScheduleofBasicandDilutiveEarningsLossperShareDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019fee81-6f98-7032-9d23-dc8717de1534" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_019fee81-6f98-797c-b730-a1b80b0fca2d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019fee81-6f98-7032-9d23-dc8717de1534" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_019fee81-6f98-797c-b730-a1b80b0fca2d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_019fee81-6f98-7315-a1e4-9ee8e1bff4d5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019fee81-6f98-7032-9d23-dc8717de1534" xlink:to="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_019fee81-6f98-7315-a1e4-9ee8e1bff4d5" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/MergerwithArchScheduleofAllocationofAggregatePurchasePriceDetails" xlink:type="simple" xlink:href="cnr-20260930.xsd#MergerwithArchScheduleofAllocationofAggregatePurchasePriceDetails"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/MergerwithArchScheduleofAllocationofAggregatePurchasePriceDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_019fee81-6f98-7556-833e-171c1748cd1b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-784b-aab6-2581f52d6152" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_019fee81-6f98-7556-833e-171c1748cd1b" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-784b-aab6-2581f52d6152" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019fee81-6f98-7135-bf6d-22c30d062b55" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_019fee81-6f98-7556-833e-171c1748cd1b" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019fee81-6f98-7135-bf6d-22c30d062b55" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_019fee81-6f98-7d11-9f72-57ceaa0d8a5b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_EffectiveSettlementOfPreExistingRelationships_019fee81-6f98-7bf9-8b17-9e63a7fe588c" xlink:href="cnr-20260930.xsd#cnr_EffectiveSettlementOfPreExistingRelationships"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationConsiderationTransferred1_019fee81-6f98-7d11-9f72-57ceaa0d8a5b" xlink:to="loc_cnr_EffectiveSettlementOfPreExistingRelationships_019fee81-6f98-7bf9-8b17-9e63a7fe588c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_019fee81-6f98-76f2-bafd-ce772e84cd02" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationConsiderationTransferred1_019fee81-6f98-7d11-9f72-57ceaa0d8a5b" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_019fee81-6f98-76f2-bafd-ce772e84cd02" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019fee81-6f98-777f-99f5-3313da061872" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_019fee81-6f98-75e3-a3e8-723f8c1ee0a2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019fee81-6f98-777f-99f5-3313da061872" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_019fee81-6f98-75e3-a3e8-723f8c1ee0a2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_019fee81-6f98-78f8-bd0f-dcefb810974f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019fee81-6f98-777f-99f5-3313da061872" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_019fee81-6f98-78f8-bd0f-dcefb810974f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFundsForAssetRetirementObligations_019fee81-6f98-7d8e-b512-c2439d81f886" xlink:href="cnr-20260930.xsd#cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFundsForAssetRetirementObligations"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019fee81-6f98-777f-99f5-3313da061872" xlink:to="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFundsForAssetRetirementObligations_019fee81-6f98-7d8e-b512-c2439d81f886" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_019fee81-6f98-7bfb-92cf-a2252f4dfd4e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019fee81-6f98-777f-99f5-3313da061872" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_019fee81-6f98-7bfb-92cf-a2252f4dfd4e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_019fee81-6f98-76eb-b1e9-5fc15fdedbed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019fee81-6f98-777f-99f5-3313da061872" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_019fee81-6f98-76eb-b1e9-5fc15fdedbed" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsShortTermInvestments_019fee81-6f98-7f31-903b-beb8ac4bb1b6" xlink:href="cnr-20260930.xsd#cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsShortTermInvestments"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019fee81-6f98-777f-99f5-3313da061872" xlink:to="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsShortTermInvestments_019fee81-6f98-7f31-903b-beb8ac4bb1b6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_019fee81-6f98-7797-8115-e5190f2567bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019fee81-6f98-777f-99f5-3313da061872" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_019fee81-6f98-7797-8115-e5190f2567bc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther_019fee81-6f98-7443-b6a0-7d049a3c26e9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019fee81-6f98-777f-99f5-3313da061872" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther_019fee81-6f98-7443-b6a0-7d049a3c26e9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOtherReceivablesNet_019fee81-6f98-75f8-9f1b-3e9acbe0c598" xlink:href="cnr-20260930.xsd#cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOtherReceivablesNet"/>
    <link:calculationArc order="9" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019fee81-6f98-777f-99f5-3313da061872" xlink:to="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOtherReceivablesNet_019fee81-6f98-75f8-9f1b-3e9acbe0c598" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-7404-b354-7c6dbbbf2d75" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPensionBenefits_019fee81-6f98-7446-8c4d-a307d3f35de7" xlink:href="cnr-20260930.xsd#cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPensionBenefits"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-7404-b354-7c6dbbbf2d75" xlink:to="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPensionBenefits_019fee81-6f98-7446-8c4d-a307d3f35de7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPostretirementBenefitsOtherThanPensions_019fee81-6f98-7090-9719-67b2978bf995" xlink:href="cnr-20260930.xsd#cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPostretirementBenefitsOtherThanPensions"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-7404-b354-7c6dbbbf2d75" xlink:to="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPostretirementBenefitsOtherThanPensions_019fee81-6f98-7090-9719-67b2978bf995" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_019fee81-6f98-7a1b-95aa-bf6d7b8e38dc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-7404-b354-7c6dbbbf2d75" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_019fee81-6f98-7a1b-95aa-bf6d7b8e38dc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_019fee81-6f98-79da-b9c9-ba5bff723ebe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-7404-b354-7c6dbbbf2d75" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_019fee81-6f98-79da-b9c9-ba5bff723ebe" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherAccruedLiabilities_019fee81-6f98-727f-9cea-91f7b8d2c3aa" xlink:href="cnr-20260930.xsd#cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherAccruedLiabilities"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-7404-b354-7c6dbbbf2d75" xlink:to="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherAccruedLiabilities_019fee81-6f98-727f-9cea-91f7b8d2c3aa" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedWorkersCompensation_019fee81-6f98-7b59-a213-4e6e3d4bde7b" xlink:href="cnr-20260930.xsd#cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedWorkersCompensation"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-7404-b354-7c6dbbbf2d75" xlink:to="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedWorkersCompensation_019fee81-6f98-7b59-a213-4e6e3d4bde7b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPneumoconiosisBenefits_019fee81-6f98-72f3-aa2c-212f3b033068" xlink:href="cnr-20260930.xsd#cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPneumoconiosisBenefits"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-7404-b354-7c6dbbbf2d75" xlink:to="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPneumoconiosisBenefits_019fee81-6f98-72f3-aa2c-212f3b033068" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetRetirementObligations_019fee81-6f98-7ad0-89ee-ef8c5b2b731f" xlink:href="cnr-20260930.xsd#cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetRetirementObligations"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-7404-b354-7c6dbbbf2d75" xlink:to="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetRetirementObligations_019fee81-6f98-7ad0-89ee-ef8c5b2b731f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLongTermDebt_019fee81-6f98-7ab4-b8e1-5b3eaf70fcc2" xlink:href="cnr-20260930.xsd#cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLongTermDebt"/>
    <link:calculationArc order="9" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-7404-b354-7c6dbbbf2d75" xlink:to="loc_cnr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLongTermDebt_019fee81-6f98-7ab4-b8e1-5b3eaf70fcc2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities_019fee81-6f98-7f91-9976-47a16c5287dc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities"/>
    <link:calculationArc order="10" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-7404-b354-7c6dbbbf2d75" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities_019fee81-6f98-7f91-9976-47a16c5287dc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesLongTermDebt_019fee81-6f98-7623-a899-12ed85d2e4ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesLongTermDebt"/>
    <link:calculationArc order="11" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019fee81-6f98-7404-b354-7c6dbbbf2d75" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesLongTermDebt_019fee81-6f98-7623-a899-12ed85d2e4ba" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/ComponentsofPensionandOtherPostretirementBenefitPlansNetPeriodicBenefitCostsDetails" xlink:type="simple" xlink:href="cnr-20260930.xsd#ComponentsofPensionandOtherPostretirementBenefitPlansNetPeriodicBenefitCostsDetails"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/ComponentsofPensionandOtherPostretirementBenefitPlansNetPeriodicBenefitCostsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019fee81-6f98-7e10-bf2e-5236d089f371" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanServiceCost_019fee81-6f98-712a-8361-595c9a5d25bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanServiceCost"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019fee81-6f98-7e10-bf2e-5236d089f371" xlink:to="loc_us-gaap_DefinedBenefitPlanServiceCost_019fee81-6f98-712a-8361-595c9a5d25bb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanInterestCost_019fee81-6f98-7049-86cd-78a7ef9559f5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanInterestCost"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019fee81-6f98-7e10-bf2e-5236d089f371" xlink:to="loc_us-gaap_DefinedBenefitPlanInterestCost_019fee81-6f98-7049-86cd-78a7ef9559f5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_019fee81-6f98-735c-8641-69d28bfdc1ae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019fee81-6f98-7e10-bf2e-5236d089f371" xlink:to="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_019fee81-6f98-735c-8641-69d28bfdc1ae" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_019fee81-6f98-7da8-993a-977af968ae89" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019fee81-6f98-7e10-bf2e-5236d089f371" xlink:to="loc_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_019fee81-6f98-7da8-993a-977af968ae89" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_019fee81-6f98-7c08-bef5-213ab497db83" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019fee81-6f98-7e10-bf2e-5236d089f371" xlink:to="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_019fee81-6f98-7c08-bef5-213ab497db83" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/ComponentsofCoalWorkersPneumoconiosisCWPandWorkersCompensationNetPeriodicBenefitCostsDetails" xlink:type="simple" xlink:href="cnr-20260930.xsd#ComponentsofCoalWorkersPneumoconiosisCWPandWorkersCompensationNetPeriodicBenefitCostsDetails"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/ComponentsofCoalWorkersPneumoconiosisCWPandWorkersCompensationNetPeriodicBenefitCostsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_cnr_DefinedBenefitPlanWorkersCompensationExpense_019fee81-6f98-7c72-a8d1-3908cc4ceb7c" xlink:href="cnr-20260930.xsd#cnr_DefinedBenefitPlanWorkersCompensationExpense"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019fee81-6f98-7b88-8206-56420d0f983e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_cnr_DefinedBenefitPlanWorkersCompensationExpense_019fee81-6f98-7c72-a8d1-3908cc4ceb7c" xlink:to="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019fee81-6f98-7b88-8206-56420d0f983e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_DefinedBenefitPlanWorkersCompensationExpenseInsuredPortion_019fee81-6f98-71e8-a395-f2c78932d38b" xlink:href="cnr-20260930.xsd#cnr_DefinedBenefitPlanWorkersCompensationExpenseInsuredPortion"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_cnr_DefinedBenefitPlanWorkersCompensationExpense_019fee81-6f98-7c72-a8d1-3908cc4ceb7c" xlink:to="loc_cnr_DefinedBenefitPlanWorkersCompensationExpenseInsuredPortion_019fee81-6f98-71e8-a395-f2c78932d38b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019fee81-6f98-7133-8fb6-3bf09a04f66f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_019fee81-6f98-7532-bc16-ea42e6b077da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019fee81-6f98-7133-8fb6-3bf09a04f66f" xlink:to="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_019fee81-6f98-7532-bc16-ea42e6b077da" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanServiceCost_019fee81-7042-790f-bc1c-247198fa2a63" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanServiceCost"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019fee81-6f98-7133-8fb6-3bf09a04f66f" xlink:to="loc_us-gaap_DefinedBenefitPlanServiceCost_019fee81-7042-790f-bc1c-247198fa2a63" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanInterestCost_019fee81-7042-78ae-8e57-700c92692409" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanInterestCost"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019fee81-6f98-7133-8fb6-3bf09a04f66f" xlink:to="loc_us-gaap_DefinedBenefitPlanInterestCost_019fee81-7042-78ae-8e57-700c92692409" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_StateAdministrativeFeesAndInsuranceBondPremiums_019fee81-7042-7353-a12a-c2a4b6b9d5d2" xlink:href="cnr-20260930.xsd#cnr_StateAdministrativeFeesAndInsuranceBondPremiums"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019fee81-6f98-7133-8fb6-3bf09a04f66f" xlink:to="loc_cnr_StateAdministrativeFeesAndInsuranceBondPremiums_019fee81-7042-7353-a12a-c2a4b6b9d5d2" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/CashCashEquivalentsRestrictedCashandShorttermInvestmentsScheduleofCashCashEquivalentsandRestrictedCashDetails" xlink:type="simple" xlink:href="cnr-20260930.xsd#CashCashEquivalentsRestrictedCashandShorttermInvestmentsScheduleofCashCashEquivalentsandRestrictedCashDetails"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/CashCashEquivalentsRestrictedCashandShorttermInvestmentsScheduleofCashCashEquivalentsandRestrictedCashDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_019fee81-7042-7893-9ca1-0b68a01c8db8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019fee81-7042-771c-9f6b-c3c8b6ed16bd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_019fee81-7042-7893-9ca1-0b68a01c8db8" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019fee81-7042-771c-9f6b-c3c8b6ed16bd" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashCurrent_019fee81-7042-7e1b-bdfb-3e7fd588c4f4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_019fee81-7042-7893-9ca1-0b68a01c8db8" xlink:to="loc_us-gaap_RestrictedCashCurrent_019fee81-7042-7e1b-bdfb-3e7fd588c4f4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashNoncurrent_019fee81-7042-7ec6-aa83-9fa20c7ca86c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashNoncurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_019fee81-7042-7893-9ca1-0b68a01c8db8" xlink:to="loc_us-gaap_RestrictedCashNoncurrent_019fee81-7042-7ec6-aa83-9fa20c7ca86c" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/InventoriesDetails" xlink:type="simple" xlink:href="cnr-20260930.xsd#InventoriesDetails"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/InventoriesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_019fee81-7042-7002-a650-750775f9a0dd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventorySuppliesNetOfReserves_019fee81-7042-7bdc-a835-4dc07431b5cb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventorySuppliesNetOfReserves"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_019fee81-7042-7002-a650-750775f9a0dd" xlink:to="loc_us-gaap_InventorySuppliesNetOfReserves_019fee81-7042-7bdc-a835-4dc07431b5cb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryRawMaterialsNetOfReserves_019fee81-7042-78ae-ab3b-c15a722da0da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryRawMaterialsNetOfReserves"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_019fee81-7042-7002-a650-750775f9a0dd" xlink:to="loc_us-gaap_InventoryRawMaterialsNetOfReserves_019fee81-7042-78ae-ab3b-c15a722da0da" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/PropertyPlantandEquipmentScheduleofPropertyPlantandEquipmentDetails" xlink:type="simple" xlink:href="cnr-20260930.xsd#PropertyPlantandEquipmentScheduleofPropertyPlantandEquipmentDetails"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/PropertyPlantandEquipmentScheduleofPropertyPlantandEquipmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_019fee81-7043-7e82-8499-4a60cff1e5c2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization_019fee81-7043-7266-ad9e-b1c4feacba3d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_019fee81-7043-7e82-8499-4a60cff1e5c2" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization_019fee81-7043-7266-ad9e-b1c4feacba3d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization_019fee81-7043-7f3d-bbd1-7c5e3a6c36d6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_019fee81-7043-7e82-8499-4a60cff1e5c2" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization_019fee81-7043-7f3d-bbd1-7c5e3a6c36d6" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/OtherAccruedLiabilitiesDetails" xlink:type="simple" xlink:href="cnr-20260930.xsd#OtherAccruedLiabilitiesDetails"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/OtherAccruedLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_019fee81-7043-7931-b367-db9413fe508a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAccruedLiabilitiesCurrent_019fee81-7043-7137-84e1-8f9f6aded502" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAccruedLiabilitiesCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fee81-7043-7931-b367-db9413fe508a" xlink:to="loc_us-gaap_OtherAccruedLiabilitiesCurrent_019fee81-7043-7137-84e1-8f9f6aded502" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_019fee81-7043-7606-8134-f3ee1f01ca98" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fee81-7043-7931-b367-db9413fe508a" xlink:to="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_019fee81-7043-7606-8134-f3ee1f01ca98" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WorkersCompensationLiabilityCurrent_019fee81-7043-78ff-98d3-0f32b5da5c4b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WorkersCompensationLiabilityCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fee81-7043-7931-b367-db9413fe508a" xlink:to="loc_us-gaap_WorkersCompensationLiabilityCurrent_019fee81-7043-78ff-98d3-0f32b5da5c4b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_LiabilityOtherPostretirementDefinedBenefitPlanCurrent_019fee81-7043-7e9c-9414-39b43fbbf148" xlink:href="cnr-20260930.xsd#cnr_LiabilityOtherPostretirementDefinedBenefitPlanCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fee81-7043-7931-b367-db9413fe508a" xlink:to="loc_cnr_LiabilityOtherPostretirementDefinedBenefitPlanCurrent_019fee81-7043-7e9c-9414-39b43fbbf148" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_EmployeeRelatedLiabilitiesMedicalAndDisabilityBenefitsCurrent_019fee81-7043-79dc-8596-77dc41b0f08e" xlink:href="cnr-20260930.xsd#cnr_EmployeeRelatedLiabilitiesMedicalAndDisabilityBenefitsCurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fee81-7043-7931-b367-db9413fe508a" xlink:to="loc_cnr_EmployeeRelatedLiabilitiesMedicalAndDisabilityBenefitsCurrent_019fee81-7043-79dc-8596-77dc41b0f08e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_SubsidenceLiabilityCurrent_019fee81-7043-7817-a879-acd997869b95" xlink:href="cnr-20260930.xsd#cnr_SubsidenceLiabilityCurrent"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fee81-7043-7931-b367-db9413fe508a" xlink:to="loc_cnr_SubsidenceLiabilityCurrent_019fee81-7043-7817-a879-acd997869b95" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetRetirementObligationCurrent_019fee81-7043-7073-bbac-c60c669ea961" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetRetirementObligationCurrent"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fee81-7043-7931-b367-db9413fe508a" xlink:to="loc_us-gaap_AssetRetirementObligationCurrent_019fee81-7043-7073-bbac-c60c669ea961" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccrualForTaxesOtherThanIncomeTaxesCurrent_019fee81-7043-70a4-9646-ecdb7395e2d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccrualForTaxesOtherThanIncomeTaxesCurrent"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_019fee81-7043-7931-b367-db9413fe508a" xlink:to="loc_us-gaap_AccrualForTaxesOtherThanIncomeTaxesCurrent_019fee81-7043-70a4-9646-ecdb7395e2d3" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/LongTermDebtScheduleofLongtermDebtInstrumentsDetails" xlink:type="simple" xlink:href="cnr-20260930.xsd#LongTermDebtScheduleofLongtermDebtInstrumentsDetails"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/LongTermDebtScheduleofLongtermDebtInstrumentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019fee81-7043-7a94-9a1a-c4e437e9f7fe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiability_019fee81-7043-7465-8b9a-17cfb64538a3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiability"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019fee81-7043-7a94-9a1a-c4e437e9f7fe" xlink:to="loc_us-gaap_FinanceLeaseLiability_019fee81-7043-7465-8b9a-17cfb64538a3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_019fee81-7043-7754-b022-a3e4cad45a7f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019fee81-7043-7a94-9a1a-c4e437e9f7fe" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_019fee81-7043-7754-b022-a3e4cad45a7f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnamortizedDebtIssuanceExpense_019fee81-7043-7369-b339-59380f089d78" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnamortizedDebtIssuanceExpense"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019fee81-7043-7a94-9a1a-c4e437e9f7fe" xlink:to="loc_us-gaap_UnamortizedDebtIssuanceExpense_019fee81-7043-7369-b339-59380f089d78" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/LongTermDebtScheduleofLongtermDebtInstrumentsDetails_1" xlink:type="simple" xlink:href="cnr-20260930.xsd#LongTermDebtScheduleofLongtermDebtInstrumentsDetails_1"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/LongTermDebtScheduleofLongtermDebtInstrumentsDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019fee81-7043-72a3-85ce-d7278a28f8f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_019fee81-7043-7fbb-b721-0a864a2aaee9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligations"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019fee81-7043-72a3-85ce-d7278a28f8f9" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_019fee81-7043-7fbb-b721-0a864a2aaee9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_019fee81-7043-77df-8491-120d42112d5c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019fee81-7043-72a3-85ce-d7278a28f8f9" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_019fee81-7043-77df-8491-120d42112d5c" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/CommitmentsandContingentLiabilitiesScheduleofGuarantorObligationsDetails" xlink:type="simple" xlink:href="cnr-20260930.xsd#CommitmentsandContingentLiabilitiesScheduleofGuarantorObligationsDetails"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/CommitmentsandContingentLiabilitiesScheduleofGuarantorObligationsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsMaximumExposure_019fee81-7043-7446-860c-d69285ba5e3b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsMaximumExposure"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_GuarantorObligationsMaximumExposureUndiscountedDueInNextTwelveMonths_019fee81-7043-743c-9f5e-21b841056ef0" xlink:href="cnr-20260930.xsd#cnr_GuarantorObligationsMaximumExposureUndiscountedDueInNextTwelveMonths"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_GuaranteeObligationsMaximumExposure_019fee81-7043-7446-860c-d69285ba5e3b" xlink:to="loc_cnr_GuarantorObligationsMaximumExposureUndiscountedDueInNextTwelveMonths_019fee81-7043-743c-9f5e-21b841056ef0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_GuarantorObligationsMaximumExposureUndiscountedDueInSecondAndThirdYear_019fee81-7043-790b-8db2-20a05228f907" xlink:href="cnr-20260930.xsd#cnr_GuarantorObligationsMaximumExposureUndiscountedDueInSecondAndThirdYear"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_GuaranteeObligationsMaximumExposure_019fee81-7043-7446-860c-d69285ba5e3b" xlink:to="loc_cnr_GuarantorObligationsMaximumExposureUndiscountedDueInSecondAndThirdYear_019fee81-7043-790b-8db2-20a05228f907" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_GuarantorObligationsMaximumExposureUndiscountedDueInFourthAndFifthYear_019fee81-7043-7ff7-af5c-88b68c636555" xlink:href="cnr-20260930.xsd#cnr_GuarantorObligationsMaximumExposureUndiscountedDueInFourthAndFifthYear"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_GuaranteeObligationsMaximumExposure_019fee81-7043-7446-860c-d69285ba5e3b" xlink:to="loc_cnr_GuarantorObligationsMaximumExposureUndiscountedDueInFourthAndFifthYear_019fee81-7043-7ff7-af5c-88b68c636555" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_GuarantorObligationsMaximumExposureUndiscountedDueAfterFifthYear_019fee81-7043-70bc-a2a2-5f61a0242a72" xlink:href="cnr-20260930.xsd#cnr_GuarantorObligationsMaximumExposureUndiscountedDueAfterFifthYear"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_GuaranteeObligationsMaximumExposure_019fee81-7043-7446-860c-d69285ba5e3b" xlink:to="loc_cnr_GuarantorObligationsMaximumExposureUndiscountedDueAfterFifthYear_019fee81-7043-70bc-a2a2-5f61a0242a72" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.corenaturalresources.com/role/SegmentInformationScheduleofSegmentReportingInformationbySegmentDetails" xlink:type="simple" xlink:href="cnr-20260930.xsd#SegmentInformationScheduleofSegmentReportingInformationbySegmentDetails"/>
  <link:calculationLink xlink:role="http://www.corenaturalresources.com/role/SegmentInformationScheduleofSegmentReportingInformationbySegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-7043-7b68-8a5e-767d8f38b3ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_ReconciliationOfSegmentInformationOtherProfitLoss_019fee81-7043-77ff-8a9c-5b7e620776d9" xlink:href="cnr-20260930.xsd#cnr_ReconciliationOfSegmentInformationOtherProfitLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-7043-7b68-8a5e-767d8f38b3ff" xlink:to="loc_cnr_ReconciliationOfSegmentInformationOtherProfitLoss_019fee81-7043-77ff-8a9c-5b7e620776d9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_019fee81-7043-7158-bde6-cbe5dc35cc60" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-7043-7b68-8a5e-767d8f38b3ff" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_019fee81-7043-7158-bde6-cbe5dc35cc60" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_019fee81-7043-765e-8488-d62bdd9ae42c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-7043-7b68-8a5e-767d8f38b3ff" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_019fee81-7043-765e-8488-d62bdd9ae42c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_019fee81-7043-7625-9678-280c985f19c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-7043-7b68-8a5e-767d8f38b3ff" xlink:to="loc_us-gaap_InterestExpenseNonoperating_019fee81-7043-7625-9678-280c985f19c9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeInterest_019fee81-7043-7b28-92ef-26352bb90aed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIncomeInterest"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-7043-7b68-8a5e-767d8f38b3ff" xlink:to="loc_us-gaap_InvestmentIncomeInterest_019fee81-7043-7b28-92ef-26352bb90aed" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PensionAndOtherPostretirementBenefitExpense_019fee81-7043-7d61-b17c-e56d3f224f0e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PensionAndOtherPostretirementBenefitExpense"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-7043-7b68-8a5e-767d8f38b3ff" xlink:to="loc_us-gaap_PensionAndOtherPostretirementBenefitExpense_019fee81-7043-7d61-b17c-e56d3f224f0e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_ClosedAndIdleMineCosts_019fee81-7043-773d-9214-891b88c01764" xlink:href="cnr-20260930.xsd#cnr_ClosedAndIdleMineCosts"/>
    <link:calculationArc order="7" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-7043-7b68-8a5e-767d8f38b3ff" xlink:to="loc_cnr_ClosedAndIdleMineCosts_019fee81-7043-773d-9214-891b88c01764" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_OtherOperatingIncomeExpenseNetAdjusted_019fee81-7043-7db1-878c-c19c88a007be" xlink:href="cnr-20260930.xsd#cnr_OtherOperatingIncomeExpenseNetAdjusted"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-7043-7b68-8a5e-767d8f38b3ff" xlink:to="loc_cnr_OtherOperatingIncomeExpenseNetAdjusted_019fee81-7043-7db1-878c-c19c88a007be" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_019fee81-7043-75c2-8867-3321fc048b1a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:calculationArc order="9" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-7043-7b68-8a5e-767d8f38b3ff" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_019fee81-7043-75c2-8867-3321fc048b1a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_AdjustedEBITDA_019fee81-7043-7701-b2a2-ded5166bbb98" xlink:href="cnr-20260930.xsd#cnr_AdjustedEBITDA"/>
    <link:calculationArc order="10" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-7043-7b68-8a5e-767d8f38b3ff" xlink:to="loc_cnr_AdjustedEBITDA_019fee81-7043-7701-b2a2-ded5166bbb98" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_019fee81-7043-7118-8c81-e58f9f82deb0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:calculationArc order="11" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019fee81-7043-7b68-8a5e-767d8f38b3ff" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_019fee81-7043-7118-8c81-e58f9f82deb0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_AdjustedEBITDA_019fee81-7043-7cc7-9e3f-afd8ad0e8c9f" xlink:href="cnr-20260930.xsd#cnr_AdjustedEBITDA"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019fee81-7043-7e1d-b3c0-937a83868726" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_cnr_AdjustedEBITDA_019fee81-7043-7cc7-9e3f-afd8ad0e8c9f" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019fee81-7043-7e1d-b3c0-937a83868726" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_CashCostsOfRevenue_019fee81-7043-73d1-a895-675b245be0de" xlink:href="cnr-20260930.xsd#cnr_CashCostsOfRevenue"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_cnr_AdjustedEBITDA_019fee81-7043-7cc7-9e3f-afd8ad0e8c9f" xlink:to="loc_cnr_CashCostsOfRevenue_019fee81-7043-73d1-a895-675b245be0de" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_cnr_TransportationExpense_019fee81-7043-7f4e-81df-2b238a446b45" xlink:href="cnr-20260930.xsd#cnr_TransportationExpense"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_cnr_AdjustedEBITDA_019fee81-7043-7cc7-9e3f-afd8ad0e8c9f" xlink:to="loc_cnr_TransportationExpense_019fee81-7043-7f4e-81df-2b238a446b45" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingOtherItemAmount_019fee81-7043-7888-8d25-8821585a0c9e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingOtherItemAmount"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_cnr_AdjustedEBITDA_019fee81-7043-7cc7-9e3f-afd8ad0e8c9f" xlink:to="loc_us-gaap_SegmentReportingOtherItemAmount_019fee81-7043-7888-8d25-8821585a0c9e" xlink:type="arc"/>
  </link:calculationLink>
</link:linkbase>
