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  <xs:element id="cmc_A5.750SeniorUnsecuredNotesDueNovember2033Member" abstract="true" name="A5.750SeniorUnsecuredNotesDueNovember2033Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_A6.000SeniorUnsecuredNotesDueDecember2035Member" abstract="true" name="A6.000SeniorUnsecuredNotesDueDecember2035Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_Series2022BondsDue2047Member" abstract="true" name="Series2022BondsDue2047Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_Series2025BondsDue2032Member" abstract="true" name="Series2025BondsDue2032Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_OtherDebtMember" abstract="true" name="OtherDebtMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_FinanceLeasesMember" abstract="true" name="FinanceLeasesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_LongTermDebtAndFinanceLeaseObligationsNet" abstract="false" name="LongTermDebtAndFinanceLeaseObligationsNet" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmc_A2033NotesAnd2035NotesMember" abstract="true" name="A2033NotesAnd2035NotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_RevolverSecondAmendmentMember" abstract="true" name="RevolverSecondAmendmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_ThirdAmendmentMember" abstract="true" name="ThirdAmendmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_PolandTermLoanMember" abstract="true" name="PolandTermLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_PolandProgramMember" abstract="true" name="PolandProgramMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_BackstopFacilityMember" abstract="true" name="BackstopFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_BridgeFacilityMember" abstract="true" name="BridgeFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_CmcpMember" abstract="true" name="CmcpMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_TransferofAccountsReceivableProgramFaceAmount" abstract="false" name="TransferofAccountsReceivableProgramFaceAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmc_CopperMember" abstract="true" name="CopperMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_EnergyFloatingRate" abstract="false" name="EnergyFloatingRate" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmc_QualifyingAdvancedEnergyProjectTaxCredit" abstract="false" name="QualifyingAdvancedEnergyProjectTaxCredit" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="cmc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquivalentSharesExpectedToVest" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquivalentSharesExpectedToVest" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="cmc_EarningsPerShareBasicAndDiluted1Abstract" abstract="true" name="EarningsPerShareBasicAndDiluted1Abstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="cmc_CerclaSitesMember" abstract="true" name="CerclaSitesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_SegmentEliminationsMember" abstract="true" name="SegmentEliminationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_RawMaterialProductsMember" abstract="true" name="RawMaterialProductsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_SteelProductsMember" abstract="true" name="SteelProductsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_DownstreamProductsMember" abstract="true" name="DownstreamProductsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_ConstructionProductsMember" abstract="true" name="ConstructionProductsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_GroundStabilizationProductsMember" abstract="true" name="GroundStabilizationProductsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_OtherProductMember" abstract="true" name="OtherProductMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_PrecastProductsMember" abstract="true" name="PrecastProductsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="cmc_AdjustedOperatingProfitLossFromContinuingOperation" abstract="false" name="AdjustedOperatingProfitLossFromContinuingOperation" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
