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  <xs:element id="usar_ContractWithCustomerLiabilityRevenueRecognizedExcludingOpeningBalance" abstract="false" name="ContractWithCustomerLiabilityRevenueRecognizedExcludingOpeningBalance" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_ContractWithCustomerLiabilityCashReceipts" abstract="false" name="ContractWithCustomerLiabilityCashReceipts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_ContractWithCustomerLiabilityIncreaseDecreaseFromTranslationAdjustments" abstract="false" name="ContractWithCustomerLiabilityIncreaseDecreaseFromTranslationAdjustments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="usar_BarclaysTradeLoanFacilityMember" abstract="true" name="BarclaysTradeLoanFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_NotePayableLineItems" abstract="true" name="NotePayableLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="usar_HatchNoteFacilityMember" abstract="true" name="HatchNoteFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_NoncashOrPartNoncashTransactionIssuanceOfGovernmentGrantWarrants" abstract="false" name="NoncashOrPartNoncashTransactionIssuanceOfGovernmentGrantWarrants" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="usar_TexasMineralResourcesCorporationMember" abstract="true" name="TexasMineralResourcesCorporationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_RoundTopMountainDevelopmentLLCMember" abstract="true" name="RoundTopMountainDevelopmentLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_VariableInterestEntityDetailsLineItems" abstract="true" name="VariableInterestEntityDetailsLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="usar_AssetAcquisitionPercentageOfOutstandingSharesAcquired" abstract="false" name="AssetAcquisitionPercentageOfOutstandingSharesAcquired" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="usar_AssetAcquisitionEquityInterestAcquiredShares" abstract="false" name="AssetAcquisitionEquityInterestAcquiredShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="usar_BusinessCombinationVotingEquityInterestAcquiredPercentageOwnershipChangeNoOfBasisPointOwnershipChange" abstract="false" name="BusinessCombinationVotingEquityInterestAcquiredPercentageOwnershipChangeNoOfBasisPointOwnershipChange" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="usar_TexasMineralResourceCorpMember" abstract="true" name="TexasMineralResourceCorpMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_MineralInterests" abstract="false" name="MineralInterests" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_LitigationMember" abstract="true" name="LitigationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_WheatRidgeColoradoMember" abstract="true" name="WheatRidgeColoradoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_WashingtonD.C.Member" abstract="true" name="WashingtonD.C.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_LeaseExpirationPeriodAxis" abstract="true" name="LeaseExpirationPeriodAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="usar_LeaseExpirationPeriodDomain" abstract="true" name="LeaseExpirationPeriodDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_March2028Member" abstract="true" name="March2028Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_EquipmentPurchaseOrderMember" abstract="true" name="EquipmentPurchaseOrderMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_UndesignatedPreferredStockMember" abstract="true" name="UndesignatedPreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_TotalAuthorized" abstract="false" name="TotalAuthorized" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="usar_MezzanineAndStockholdersEquityTable" abstract="true" name="MezzanineAndStockholdersEquityTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="usar_A1.50BillionPrivateInvestmentInPublicEquityMember" abstract="true" name="A1.50BillionPrivateInvestmentInPublicEquityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_USDeptOfCommerceMember" abstract="true" name="USDeptOfCommerceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_DOCWarrantMember" abstract="true" name="DOCWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_MezzanineAndStockholdersEquityLineItems" abstract="true" name="MezzanineAndStockholdersEquityLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="usar_CommonStockAndWarrantsSharesIssued" abstract="false" name="CommonStockAndWarrantsSharesIssued" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="usar_EquityBasedCompensationScheduleofCompensationExpenseDetailsTable" abstract="true" name="EquityBasedCompensationScheduleofCompensationExpenseDetailsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="usar_PerformanceRestrictedStockUnitsMember" abstract="true" name="PerformanceRestrictedStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_IncentiveUnitsMember" abstract="true" name="IncentiveUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_NetIncomeLossPerShareDetailsTable" abstract="true" name="NetIncomeLossPerShareDetailsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="usar_ConvertibleSeriesAPreferredStockMember" abstract="true" name="ConvertibleSeriesAPreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_SeriesAWarrantsMember" abstract="true" name="SeriesAWarrantsMember" 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_GovernmentGrantWarrantsMember" abstract="true" name="GovernmentGrantWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_CustomerOneMember" abstract="true" name="CustomerOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_CustomerTwoMember" abstract="true" name="CustomerTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_CustomerThreeMember" abstract="true" name="CustomerThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_CustomerFourMember" abstract="true" name="CustomerFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_AllOtherCustomersMember" abstract="true" name="AllOtherCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_USARareEarthLLCMember" abstract="true" name="USARareEarthLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_CaresterSASInvestmentMember" abstract="true" name="CaresterSASInvestmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_SVREHoldingsLtdMember" abstract="true" name="SVREHoldingsLtdMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_CommonStockTrancheOneMember" abstract="true" name="CommonStockTrancheOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_CommonStockTrancheTwoMember" abstract="true" name="CommonStockTrancheTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_BusinessCombinationPricePerShareMarketPriceConditionConsecutiveTradingDays" abstract="false" name="BusinessCombinationPricePerShareMarketPriceConditionConsecutiveTradingDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="usar_EquitySecuritiesFVNIAcquiredConsiderationTransferred" abstract="false" name="EquitySecuritiesFVNIAcquiredConsiderationTransferred" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_EquitySecuritiesFVNIAcquiredConsiderationTransferredEquity" abstract="false" name="EquitySecuritiesFVNIAcquiredConsiderationTransferredEquity" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_FundingTypeAxis" abstract="true" name="FundingTypeAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="usar_FundingTypeDomain" abstract="true" name="FundingTypeDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_DirectFundingAwardMember" abstract="true" name="DirectFundingAwardMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_LoanGuaranteeAgreementMember" abstract="true" name="LoanGuaranteeAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_ClassOfWarrantOrRightFairValuePriceOfWarrantsOrRights" abstract="false" name="ClassOfWarrantOrRightFairValuePriceOfWarrantsOrRights" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="usar_StockAndWarrantsIssuedDuringPeriodGovernmentGrantProgramValue" abstract="false" name="StockAndWarrantsIssuedDuringPeriodGovernmentGrantProgramValue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_GovernmentAssistanceCovenantLockUpPeriod" abstract="false" name="GovernmentAssistanceCovenantLockUpPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="usar_ProceedsFromGovernmentGrants" abstract="false" name="ProceedsFromGovernmentGrants" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_DebtInstrumentCommitmentFeePercentage" abstract="false" name="DebtInstrumentCommitmentFeePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="usar_DebtInstrumentAnnualTickingFeePercentage" abstract="false" name="DebtInstrumentAnnualTickingFeePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="usar_HootonParkMember" abstract="true" name="HootonParkMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
