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        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
    </xs:appinfo>
  </xs:annotation>
  <xs:element id="usar_SeriesACumulativeConvertiblePreferredStockSubjectToPossibleRedemptionMember" abstract="true" name="SeriesACumulativeConvertiblePreferredStockSubjectToPossibleRedemptionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_AuditInformationAbstract" abstract="true" name="AuditInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="usar_MineralInterestsAtCost" abstract="false" name="MineralInterestsAtCost" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_EquipmentDeposits" abstract="false" name="EquipmentDeposits" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_DeferredGrants" abstract="false" name="DeferredGrants" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_EarnoutLiabilities" abstract="false" name="EarnoutLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_TemporaryEquityBeforeSubscriptionReceivable" abstract="false" name="TemporaryEquityBeforeSubscriptionReceivable" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_TemporaryEquityPaymentInKindDividendPercentage" abstract="false" name="TemporaryEquityPaymentInKindDividendPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="usar_NumberOfSharesUsedInPerShareCalculationsAbstract" abstract="true" name="NumberOfSharesUsedInPerShareCalculationsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="usar_MezzanineEquitySubscriptionReceivableMember" abstract="true" name="MezzanineEquitySubscriptionReceivableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_SubscriptionReceivabeMember" abstract="true" name="SubscriptionReceivabeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_RetroactiveApplicationOfRecapitalizationMember" abstract="true" name="RetroactiveApplicationOfRecapitalizationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_ClassCConvertiblePreferredStockMember" abstract="true" name="ClassCConvertiblePreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_ClassC1ConvertiblePreferredStockMember" abstract="true" name="ClassC1ConvertiblePreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_TemporaryEquityAccretionOfDividendsShares" abstract="false" name="TemporaryEquityAccretionOfDividendsShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="usar_TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" abstract="false" name="TemporaryEquityStockIssuedDuringPeriodSharesNewIssues" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="usar_TemporaryEquityStockIssuedDuringPeriodSharesReverseStockSplits" abstract="false" name="TemporaryEquityStockIssuedDuringPeriodSharesReverseStockSplits" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="usar_TemporaryEquityStockIssuedDuringPeriodValueReverseStockSplits" abstract="false" name="TemporaryEquityStockIssuedDuringPeriodValueReverseStockSplits" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_TemporaryEquityStockIssuedIssuanceCosts" abstract="false" name="TemporaryEquityStockIssuedIssuanceCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_TemporaryEquityStockRedeemedOrCalledDuringPeriodValue" abstract="false" name="TemporaryEquityStockRedeemedOrCalledDuringPeriodValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_StockIssuedDuringPeriodValueExtinguishmentOfNotePayable" abstract="false" name="StockIssuedDuringPeriodValueExtinguishmentOfNotePayable" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_StockIssuedDuringPeriodSharesStockDividend" abstract="false" name="StockIssuedDuringPeriodSharesStockDividend" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="usar_StockIssuedDuringPeriodValueReverseStockSplits" abstract="false" name="StockIssuedDuringPeriodValueReverseStockSplits" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_StockIssuedDuringPeriodSharesExerciseOfWarrants" abstract="false" name="StockIssuedDuringPeriodSharesExerciseOfWarrants" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="usar_StockIssuedDuringPeriodValuesExerciseOfWarrants" abstract="false" name="StockIssuedDuringPeriodValuesExerciseOfWarrants" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_StockIssuedDuringPeriodSharesPrivateInvestmentInPublicEquity" abstract="false" name="StockIssuedDuringPeriodSharesPrivateInvestmentInPublicEquity" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="usar_StockIssuedDuringPeriodValuesPrivateInvestmentInPublicEquity" abstract="false" name="StockIssuedDuringPeriodValuesPrivateInvestmentInPublicEquity" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_AdjustmentsToAdditionalPaidInCapitalEstablishmentOfEarnOutLiabilities" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalEstablishmentOfEarnOutLiabilities" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_StockIssuedDuringPeriodValueConversionOfPreferredInvestorWarrantsIntoLiabilityClassifiedWarrants" abstract="false" name="StockIssuedDuringPeriodValueConversionOfPreferredInvestorWarrantsIntoLiabilityClassifiedWarrants" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_AdjustmentsToAdditionalPaidInCapitalForwardPurchaseAgreements" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalForwardPurchaseAgreements" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_AdjustmentsToAdditionalPaidInCapitalEarlyTerminationsOfForwardPurchaseAgreements" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalEarlyTerminationsOfForwardPurchaseAgreements" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_AdjustmentsToPaidInCapitalAccretionOfForwardPurchaseAgreements" abstract="false" name="AdjustmentsToPaidInCapitalAccretionOfForwardPurchaseAgreements" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_NoncontrollingInterestDilution" abstract="false" name="NoncontrollingInterestDilution" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_SeriesA1A2PreferredStockMember" abstract="true" name="SeriesA1A2PreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_ClassCC1ConvertiblePreferredStockMember" abstract="true" name="ClassCC1ConvertiblePreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_ClassA1A2ConvertiblePreferredStockMember" abstract="true" name="ClassA1A2ConvertiblePreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_LitigationSettlementThroughStockIssuance" abstract="false" name="LitigationSettlementThroughStockIssuance" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_GainLossOnFairMarketValueOfConvertibleDebt" abstract="false" name="GainLossOnFairMarketValueOfConvertibleDebt" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_PrepaymentOfForwardPurchaseAgreements" abstract="false" name="PrepaymentOfForwardPurchaseAgreements" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_ProceedsFromTerminationOfForwardPurchaseAgreements" abstract="false" name="ProceedsFromTerminationOfForwardPurchaseAgreements" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_PaymentOfSecuritiesIssuanceCosts" abstract="false" name="PaymentOfSecuritiesIssuanceCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_ProceedsFromFinancedLeases" abstract="false" name="ProceedsFromFinancedLeases" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_DeferredOfferingCostsPolicyTextBlock" abstract="false" name="DeferredOfferingCostsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_ChangesInOwnershipInterestWithoutLossOfControlPolicyTextBlock" abstract="false" name="ChangesInOwnershipInterestWithoutLossOfControlPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_EarnoutLiabilitiesPolicyTextBlock" abstract="false" name="EarnoutLiabilitiesPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_WarrantsPolicyTextBlock" abstract="false" name="WarrantsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_DividendsPolicyTextBlock" abstract="false" name="DividendsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_ScheduleOfEstimatedUsefulLivesOfTheRelatedAssetTableTextBlock" abstract="false" name="ScheduleOfEstimatedUsefulLivesOfTheRelatedAssetTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_ScheduleOfEquityInstrumentsOutstandingTableTextBlock" abstract="false" name="ScheduleOfEquityInstrumentsOutstandingTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_ScheduleOfNetProceedsFromMergerTableTextBlockTableTextBlock" abstract="false" name="ScheduleOfNetProceedsFromMergerTableTextBlockTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_LesseeSupplementalBalanceSheetInformationTableTextBlock" abstract="false" name="LesseeSupplementalBalanceSheetInformationTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_ScheduleOfActiveFinanceLeasesTableTextBlock" abstract="false" name="ScheduleOfActiveFinanceLeasesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_ScheduleOfMaterialPropertyLeasesTableTextBlock" abstract="false" name="ScheduleOfMaterialPropertyLeasesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_ScheduleOfWarrantsToAcquireCommonStockTableTextBlock" abstract="false" name="ScheduleOfWarrantsToAcquireCommonStockTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_ScheduleOfConversionOfCommonStockTableTextBlock" abstract="false" name="ScheduleOfConversionOfCommonStockTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_ScheduleOfShareBasedPaymentArrangementNonvestedAwardExcludingOptionCostNotYetRecognizedTableTextBlock" abstract="false" name="ScheduleOfShareBasedPaymentArrangementNonvestedAwardExcludingOptionCostNotYetRecognizedTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_DeferredTaxAssetsChangeInValuationAllowanceTableTextBlock" abstract="false" name="DeferredTaxAssetsChangeInValuationAllowanceTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="usar_SummaryofSignificantAccountingPoliciesScheduleofEstimatedUsefulLivesoftheRelatedAssetDetailsTable" abstract="true" name="SummaryofSignificantAccountingPoliciesScheduleofEstimatedUsefulLivesoftheRelatedAssetDetailsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="usar_ManufacturingEquipmentMember" abstract="true" name="ManufacturingEquipmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_LabEquipmentMember" abstract="true" name="LabEquipmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_SummaryofSignificantAccountingPoliciesScheduleofEstimatedUsefulLivesoftheRelatedAssetDetailsLineItems" abstract="true" name="SummaryofSignificantAccountingPoliciesScheduleofEstimatedUsefulLivesoftheRelatedAssetDetailsLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="usar_ClassA1AndClassA2Member" abstract="true" name="ClassA1AndClassA2Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_EarnoutSharesMember" abstract="true" name="EarnoutSharesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_USARareEarthIncMember" abstract="true" name="USARareEarthIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_MrMichaelBlitzerMember" abstract="true" name="MrMichaelBlitzerMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_PreDomesticationWarrantsMember" abstract="true" name="PreDomesticationWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_USAREClassAPreferredInvestorWarrantsMember" abstract="true" name="USAREClassAPreferredInvestorWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_HatchNoteMember" abstract="true" name="HatchNoteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_ConvertiblePromissoryNoteMember" abstract="true" name="ConvertiblePromissoryNoteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_BusinessCombinationAgreementMember" abstract="true" name="BusinessCombinationAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_IndianOceanRareEarthMetalsPte.Ltd.Member" abstract="true" name="IndianOceanRareEarthMetalsPte.Ltd.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_LessCommonMetalsLtd.Member" abstract="true" name="LessCommonMetalsLtd.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_EarnoutAndForwardPurchaseAgreementsMember" abstract="true" name="EarnoutAndForwardPurchaseAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_SecondTrancheMember" abstract="true" name="SecondTrancheMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_ForwardPurchaseAgreementsMember" abstract="true" name="ForwardPurchaseAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_BusinessCombinationEquityConversionRatio" abstract="false" name="BusinessCombinationEquityConversionRatio" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="usar_SubscriptionReceivable" abstract="false" name="SubscriptionReceivable" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_PercentageOfForgiveness" abstract="false" name="PercentageOfForgiveness" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="usar_AggregatePurchasePrice" abstract="false" name="AggregatePurchasePrice" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_BusinessCombinationTradingDayPeriodMinimum" abstract="false" name="BusinessCombinationTradingDayPeriodMinimum" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="usar_BusinessCombinationTradingDayPeriodConsecutive" abstract="false" name="BusinessCombinationTradingDayPeriodConsecutive" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="usar_StockIssuedDuringPeriodResetPriceMinimum" abstract="false" name="StockIssuedDuringPeriodResetPriceMinimum" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="usar_MergerTransactionScheduleofEquityInstrumentsOutstandingDetailsTable" abstract="true" name="MergerTransactionScheduleofEquityInstrumentsOutstandingDetailsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="usar_PreMergerShareholdersMember" abstract="true" name="PreMergerShareholdersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_SharesIssuedInReverseMergerRecapitalizationMember" abstract="true" name="SharesIssuedInReverseMergerRecapitalizationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_MergerTransactionScheduleofEquityInstrumentsOutstandingDetailsLineItems" abstract="true" name="MergerTransactionScheduleofEquityInstrumentsOutstandingDetailsLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="usar_PreferredStockVotingSharesOutstanding" abstract="false" name="PreferredStockVotingSharesOutstanding" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="usar_MergerTransactionScheduleofNetProceedsfromtheMergerDetailsTable" abstract="true" name="MergerTransactionScheduleofNetProceedsfromtheMergerDetailsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="usar_CashPIPEInvestmentMember" abstract="true" name="CashPIPEInvestmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_CashIPXXTrustAccountMember" abstract="true" name="CashIPXXTrustAccountMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_CashIPXXOpAccountMember" abstract="true" name="CashIPXXOpAccountMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_MergerTransactionScheduleofNetProceedsfromtheMergerDetailsLineItems" abstract="true" name="MergerTransactionScheduleofNetProceedsfromtheMergerDetailsLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="usar_TotalCashAndCashEquivalentsBeforeTheMerger" abstract="false" name="TotalCashAndCashEquivalentsBeforeTheMerger" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_TransactionCostsAllocatedToEquity" abstract="false" name="TransactionCostsAllocatedToEquity" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_FPAPrepayments" abstract="false" name="FPAPrepayments" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_OtherExpensesAndPrepayments" abstract="false" name="OtherExpensesAndPrepayments" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_TotalCashAndCashEquivalentsAfterTheMerger" abstract="false" name="TotalCashAndCashEquivalentsAfterTheMerger" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_TransactionCostAllocatedToEquity" abstract="false" name="TransactionCostAllocatedToEquity" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_NetCashUsedByUSARELLC" abstract="false" name="NetCashUsedByUSARELLC" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_NetCash" abstract="false" name="NetCash" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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</xs:schema>
