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  <xs:element id="usar_OperatingLeaseAssetsLesseeAbstract" abstract="true" name="OperatingLeaseAssetsLesseeAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="usar_LeaseRightOfUseAsset" abstract="false" name="LeaseRightOfUseAsset" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_OperatingLeaseLiabilitiesLesseeAbstract" abstract="true" name="OperatingLeaseLiabilitiesLesseeAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="usar_OperatingLeaseLiabilityIncludingLeaseDepositLiability" abstract="false" name="OperatingLeaseLiabilityIncludingLeaseDepositLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_LeaseLiability" abstract="false" name="LeaseLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_MezzanineandStockholdersEquityScheduleofWarrantstoAcquireCommonstockDetailsTable" abstract="true" name="MezzanineandStockholdersEquityScheduleofWarrantstoAcquireCommonstockDetailsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="usar_InvestorWarrantsMember" abstract="true" name="InvestorWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_SeriesAInvestorWarrantsMember" abstract="true" name="SeriesAInvestorWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_CommonStockWarrantsMember" abstract="true" name="CommonStockWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_PrefundedWarrantsMember" abstract="true" name="PrefundedWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_ClassOfWarrantOrRightPercentageIncreaseInIssuableSharesToWarrantHolders" abstract="false" name="ClassOfWarrantOrRightPercentageIncreaseInIssuableSharesToWarrantHolders" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="usar_MezzanineAndStockholdersEquityTable" abstract="true" name="MezzanineAndStockholdersEquityTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="usar_CommonStockSharesMay2025AgreementClosingDateMember" abstract="true" name="CommonStockSharesMay2025AgreementClosingDateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_CommonStockSharesSeptember2025AgreementClosingDateMember" abstract="true" name="CommonStockSharesSeptember2025AgreementClosingDateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_PIPEAgreementsMember" abstract="true" name="PIPEAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_A125MillionPrivateInvestmentInPublicEquityMember" abstract="true" name="A125MillionPrivateInvestmentInPublicEquityMember" 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_CommonStockSharesAndWarrantsIssued" abstract="false" name="CommonStockSharesAndWarrantsIssued" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="usar_ClassOfWarrantOrRightBeneficialOwnershipPercentageMaximum" abstract="false" name="ClassOfWarrantOrRightBeneficialOwnershipPercentageMaximum" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="usar_ClassOfWarrantOrRightExpirationPeriod" abstract="false" name="ClassOfWarrantOrRightExpirationPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="usar_GainLossOnIssuanceOfCommonStock" abstract="false" name="GainLossOnIssuanceOfCommonStock" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="usar_EquityBasedCompensationDetailsTable" abstract="true" name="EquityBasedCompensationDetailsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="usar_TwoThousandTwentyFourOmnibusIncentivePlanMember" abstract="true" name="TwoThousandTwentyFourOmnibusIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsRightToReceive" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsRightToReceive" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="usar_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingRightsConversionRatio" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingRightsConversionRatio" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="usar_EquityBasedCompensationScheduleofCompensationExpenseDetailsTable" abstract="true" name="EquityBasedCompensationScheduleofCompensationExpenseDetailsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <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_A2024IncentivePlanMember" abstract="true" name="A2024IncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_EquityBasedCompensationDetailsLineItems" abstract="true" name="EquityBasedCompensationDetailsLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="usar_TaxIncrementalFinancingMember" abstract="true" name="TaxIncrementalFinancingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_GovenorsFundMember" abstract="true" name="GovenorsFundMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_JobsProgramMember" abstract="true" name="JobsProgramMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_TaxExemptionPeriod" abstract="false" name="TaxExemptionPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="usar_PercentageOfCashRebateOfWagesMaximum" abstract="false" name="PercentageOfCashRebateOfWagesMaximum" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="usar_GovernmentAssistanceTransactionDurationMaximumTerm" abstract="false" name="GovernmentAssistanceTransactionDurationMaximumTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="usar_MaximumPaymentsForOtherFees" abstract="false" name="MaximumPaymentsForOtherFees" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_ClassBCommonWarrantsMember" abstract="true" name="ClassBCommonWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="usar_ClassCCommonWarrantsMember" abstract="true" name="ClassCCommonWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
