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  <xsd:element id="mcp_DebtInstrumentRedeemableDebtRedeemablePrincipalFromProceedsFromEquity" name="DebtInstrumentRedeemableDebtRedeemablePrincipalFromProceedsFromEquity" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_DebtInstrumentRedeemableDebtRedemptionPercentageOfPrincipalAmount" name="DebtInstrumentRedeemableDebtRedemptionPercentageOfPrincipalAmount" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_DebtInstrumentThresholdPercentageAboveWhichCompanyHasRightToRedeemNotes" name="DebtInstrumentThresholdPercentageAboveWhichCompanyHasRightToRedeemNotes" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_DebtInstrumentUnusedBorrowingAvailabilityContingentUponAchievingPerformanceTargets" name="DebtInstrumentUnusedBorrowingAvailabilityContingentUponAchievingPerformanceTargets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcp_DebtInstrumentsCollateralExcludedAssetsVotingStockOfForeignSubsidiariesPercentMinimum" name="DebtInstrumentsCollateralExcludedAssetsVotingStockOfForeignSubsidiariesPercentMinimum" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_DebtandLeaseFinancingCommitmentCapacity" name="DebtandLeaseFinancingCommitmentCapacity" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_DeferredFinanceCostsOwnshareLendingArrangementIssuanceCostsCapitalizedInterestCosts" name="DeferredFinanceCostsOwnshareLendingArrangementIssuanceCostsCapitalizedInterestCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_DeferredFinanceCostsOwnshareLendingArrangementIssuanceCostsInterestCostExpensed" name="DeferredFinanceCostsOwnshareLendingArrangementIssuanceCostsInterestCostExpensed" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_DeferredFinanceCostsOwnshareLendingArrangementIssuanceCostsTableTextBlock" name="DeferredFinanceCostsOwnshareLendingArrangementIssuanceCostsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_DeferredIncomeTaxExpenseBenefitDueToEliminationOfIntercompanyBalancesAndTransactions" name="DeferredIncomeTaxExpenseBenefitDueToEliminationOfIntercompanyBalancesAndTransactions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcp_DeferredIncomeTaxNoncashExpenseBenefit" name="DeferredIncomeTaxNoncashExpenseBenefit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_DeferredTaxAssetsGrossCurrentAbstract" name="DeferredTaxAssetsGrossCurrentAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_DeferredTaxAssetsGrossNoncurrentAbstract" name="DeferredTaxAssetsGrossNoncurrentAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_DeferredTaxAssetsLiabilitiesGross" name="DeferredTaxAssetsLiabilitiesGross" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcp_DeferredTaxAssetsMineralResourcesNoncurrent" name="DeferredTaxAssetsMineralResourcesNoncurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcp_DeferredTaxAssetsOtherCurrent" name="DeferredTaxAssetsOtherCurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcp_DeferredTaxAssetsOtherNoncurrent" name="DeferredTaxAssetsOtherNoncurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcp_DeferredTaxAssetsPropertyPlantandEquipmentandIntangibleAssets" name="DeferredTaxAssetsPropertyPlantandEquipmentandIntangibleAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcp_DeferredTaxAssetsTaxCreditCarryforwardsResearchAndEnergy" name="DeferredTaxAssetsTaxCreditCarryforwardsResearchAndEnergy" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcp_DeferredTaxLiabilitiesAssetRetirementObligations" name="DeferredTaxLiabilitiesAssetRetirementObligations" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcp_DeferredTaxLiabilitiesGrossCurrentAbstract" name="DeferredTaxLiabilitiesGrossCurrentAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_DeferredTaxLiabilitiesGrossNoncurrentAbstract" name="DeferredTaxLiabilitiesGrossNoncurrentAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_DeferredTaxLiabilitiesOtherCurrent" name="DeferredTaxLiabilitiesOtherCurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcp_DeferredTaxLiabilitiesOtherNoncurrent" name="DeferredTaxLiabilitiesOtherNoncurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcp_DeferredTaxLiabilitiesPropertyPlantAndEquipmentAndIntangibleAssets" name="DeferredTaxLiabilitiesPropertyPlantAndEquipmentAndIntangibleAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcp_DefinedBenefitPlanNumberofParticipants" name="DefinedBenefitPlanNumberofParticipants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_DefinedContributionPlanEmployerMatchEmployeeContributionLevelOne" name="DefinedContributionPlanEmployerMatchEmployeeContributionLevelOne" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_DefinedContributionPlanEmployerMatchEmployeeContributionLevelTwo" name="DefinedContributionPlanEmployerMatchEmployeeContributionLevelTwo" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_DefinedContributionPlanEmployerMatchLevelOne" name="DefinedContributionPlanEmployerMatchLevelOne" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_DefinedContributionPlanEmployerMatchLevelTwo" name="DefinedContributionPlanEmployerMatchLevelTwo" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_DefinedContributionPlanRequisiteServicePeriodForEmployeeVesting" name="DefinedContributionPlanRequisiteServicePeriodForEmployeeVesting" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_DefinedContributionPlanVestingPercentageOfDiscretionaryMatchingContributionAfterThreeYearsOfService" name="DefinedContributionPlanVestingPercentageOfDiscretionaryMatchingContributionAfterThreeYearsOfService" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_Definedcontributionplanaccruedexpense" name="Definedcontributionplanaccruedexpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcp_Definedcontributionplansafeharbormatchingcontributionvestingpercentage" name="Definedcontributionplansafeharbormatchingcontributionvestingpercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcp_DepositByThirdPartyNameAxis" name="DepositByThirdPartyNameAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_DepositsByThirdPartyNameDomain" name="DepositsByThirdPartyNameDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_DepositsDisclosureTextBlock" name="DepositsDisclosureTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_DepositsForConstructionInsuranceProgram" name="DepositsForConstructionInsuranceProgram" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcp_DepositsLineItems" name="DepositsLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_DepositsTable" name="DepositsTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_DepreciationDepletionAndAmortizationfromproductionandnonproduction." name="DepreciationDepletionAndAmortizationfromproductionandnonproduction." nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_Differencebetweenconsiderationtransferredtotheholderandthefairvalueofliabilitycomponent" name="Differencebetweenconsiderationtransferredtotheholderandthefairvalueofliabilitycomponent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcp_DisposalGroupIncludingDiscontinuedOperationsAssetImpairments" name="DisposalGroupIncludingDiscontinuedOperationsAssetImpairments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_DisposalGroupIncludingDiscontinuedOperationsSellingGeneralandAdministrativeExpense" name="DisposalGroupIncludingDiscontinuedOperationsSellingGeneralandAdministrativeExpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_EarlyPaymentPremiumPercentageAbstract" name="EarlyPaymentPremiumPercentageAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_EarlyPaymentPremiumPercentagePercentofPrincipalAftertoFourthAnniversary" name="EarlyPaymentPremiumPercentagePercentofPrincipalAftertoFourthAnniversary" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_EarlyPaymentPremiumPercentagePercentofPrincipalPriortoFirstAnniversary" name="EarlyPaymentPremiumPercentagePercentofPrincipalPriortoFirstAnniversary" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_EarlyPaymentPremiumPercentagePercentofPrincipalPriortoFourthAnniversary" name="EarlyPaymentPremiumPercentagePercentofPrincipalPriortoFourthAnniversary" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_EarlyPaymentPremiumPercentagePercentofPrincipalPriortoSecondAnniversary" name="EarlyPaymentPremiumPercentagePercentofPrincipalPriortoSecondAnniversary" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_EarlyPaymentPremiumPercentagePercentofPrincipalPriortoThirdAnniversary" name="EarlyPaymentPremiumPercentagePercentofPrincipalPriortoThirdAnniversary" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_EarlyPaymentPremiumPercentageResultingfromanAssetSalePercentofPrincipal" name="EarlyPaymentPremiumPercentageResultingfromanAssetSalePercentofPrincipal" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_EffectiveIncomeTaxReconciliationForeignTranslationAdjustmentsAmount" name="EffectiveIncomeTaxReconciliationForeignTranslationAdjustmentsAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_EquipmentFinancing12PercentMember" name="EquipmentFinancing12PercentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_EquityEarningsFromConsolidatedSubsidiaries" name="EquityEarningsFromConsolidatedSubsidiaries" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_EquityandCostMethodInvestmentOtherthanTemporaryImpairment" name="EquityandCostMethodInvestmentOtherthanTemporaryImpairment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_EquityandCostMethodInvestmentRollForward" name="EquityandCostMethodInvestmentRollForward" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_ExchangeableSharesConverted" name="ExchangeableSharesConverted" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_ExpectedFutureCapitalExpendituresEstimatedCapitalExpendituresInNextFiscalYear" name="ExpectedFutureCapitalExpendituresEstimatedCapitalExpendituresInNextFiscalYear" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcp_ExpectedFutureCapitalExpendituresEstimatedCapitalExpendituresYearTwo" name="ExpectedFutureCapitalExpendituresEstimatedCapitalExpendituresYearTwo" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcp_Expiringbetween2024and2032Member" name="Expiringbetween2024and2032Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_Expiringin2023Member" name="Expiringin2023Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_ExplorationRightsMember" name="ExplorationRightsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_FairValueAssumptionsApplicationofDiscountforLackofMarketabilitySharePrice" name="FairValueAssumptionsApplicationofDiscountforLackofMarketabilitySharePrice" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_FairValueInputsCustomerAttrition" name="FairValueInputsCustomerAttrition" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_FairValueInputsEquityRiskPremium" name="FairValueInputsEquityRiskPremium" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_FairValueInputsGrowthRate" name="FairValueInputsGrowthRate" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_FairValueInputsProbabilityFactor" name="FairValueInputsProbabilityFactor" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_FairValueInputsRiskPremium" name="FairValueInputsRiskPremium" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_FairValueInputsSizePremium" name="FairValueInputsSizePremium" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_FairValueOfEquityInvestmentOfBusinessAcquisition" name="FairValueOfEquityInvestmentOfBusinessAcquisition" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcp_FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItemsLineItems" name="FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItemsLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_FiniteLivedAndIndefiniteLivedIntangibleAssetsRollForward" name="FiniteLivedAndIndefiniteLivedIntangibleAssetsRollForward" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_FiniteLivedAssetsUsefulLifeMaximum" name="FiniteLivedAssetsUsefulLifeMaximum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_FiniteLivedAssetsUsefulLifeMinimum" name="FiniteLivedAssetsUsefulLifeMinimum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_FivePercentSubordinatedConvertibleNotesMember" name="FivePercentSubordinatedConvertibleNotesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_FivePointFiftyPercentConvertibleSeniorNotesDueTwoThousandEighteenMember" name="FivePointFiftyPercentConvertibleSeniorNotesDueTwoThousandEighteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_FlatFeePaidToUnderwriters" name="FlatFeePaidToUnderwriters" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_GalliumMetalMember" name="GalliumMetalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_GanzhouKeliRareEarthNewMaterialMember" name="GanzhouKeliRareEarthNewMaterialMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_GoodwillFairValueexcessoverCarryingValuePercent" name="GoodwillFairValueexcessoverCarryingValuePercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_Goodwilladditionalimpairmentlossfromfinalpurchasepriceallocation" name="Goodwilladditionalimpairmentlossfromfinalpurchasepriceallocation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_Goodwillimpairmentlossfrominitialpurchasepriceallocation" name="Goodwillimpairmentlossfrominitialpurchasepriceallocation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_ImpairmentofOtherReceivables" name="ImpairmentofOtherReceivables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_IncomeLossfromEquityMethodInvestmentsexcludingotherthantemporaryimpairment" name="IncomeLossfromEquityMethodInvestmentsexcludingotherthantemporaryimpairment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_IncomeTaxPayableDueToEliminationOfIntercompanyBalancesAndTransactions" name="IncomeTaxPayableDueToEliminationOfIntercompanyBalancesAndTransactions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcp_IndefiniteCarryforwardMember" name="IndefiniteCarryforwardMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_IngalStadeGmbhMember" name="IngalStadeGmbhMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_IntercompanyAccountsPayable" name="IntercompanyAccountsPayable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcp_IntercompanyAccountsReceivable" name="IntercompanyAccountsReceivable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcp_InterestIncomeExpenseFromIntercompanyNotesNet" name="InterestIncomeExpenseFromIntercompanyNotesNet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_IntermetallicsJapanJointVentureIMJMember" name="IntermetallicsJapanJointVentureIMJMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_InventoryConcentrateStockpilesNetOfReservesCurrent" name="InventoryConcentrateStockpilesNetOfReservesCurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcp_InventoryConcentrateStockpilesNetOfReservesNonCurrent" name="InventoryConcentrateStockpilesNetOfReservesNonCurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcp_InventoryRawMaterialsNetOfReservesNoncurrent" name="InventoryRawMaterialsNetOfReservesNoncurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcp_InventoryWritedownIncludingStockpileInventories" name="InventoryWritedownIncludingStockpileInventories" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_JiangyinJiaHuaAdvancedMaterialResourcesCoLtdMember" name="JiangyinJiaHuaAdvancedMaterialResourcesCoLtdMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_KernRiverGasTransmissionCompanyMember" name="KernRiverGasTransmissionCompanyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_LoanstoParent" name="LoanstoParent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_Magnequench12PercentTermLoanMember" name="Magnequench12PercentTermLoanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_MagneticMaterialsAndAlloysMember" name="MagneticMaterialsAndAlloysMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_MaintenanceandOtherExpansionCapitalExpendituresMember" name="MaintenanceandOtherExpansionCapitalExpendituresMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_MandatoryConvertiblePreferredStockPricePerShare" name="MandatoryConvertiblePreferredStockPricePerShare" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_MaximumPrincipalAmountofDebtSecuredbythePariPassuCollateral" name="MaximumPrincipalAmountofDebtSecuredbythePariPassuCollateral" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcp_McpExchangecoIncMember" name="McpExchangecoIncMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_MetalsMember" name="MetalsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_MineralPropertiesAndDevelopmentCostsPolicyTextBlock" name="MineralPropertiesAndDevelopmentCostsPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_MinimumLeasePaymentsSaleLeasebackTransactionsAdditionalPaymentonFiveYearAnniversary" name="MinimumLeasePaymentsSaleLeasebackTransactionsAdditionalPaymentonFiveYearAnniversary" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcp_MinimumLeasePaymentsSaleLeasebackTransactionsPossiblePaymentAdjustmentAdditionalPaymentonFiveYearAnniversary" name="MinimumLeasePaymentsSaleLeasebackTransactionsPossiblePaymentAdjustmentAdditionalPaymentonFiveYearAnniversary" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcp_MinimumLeasePaymentsSaleLeasebackTransactionsPossiblePaymentAdjustmentYearsTwoThroughFive" name="MinimumLeasePaymentsSaleLeasebackTransactionsPossiblePaymentAdjustmentYearsTwoThroughFive" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcp_MiningequipmentundercapitalleaseMember" name="MiningequipmentundercapitalleaseMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_MitsubishiCorporationMember" name="MitsubishiCorporationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_MolycorpCanadaAndMolycorpSilmetMember" name="MolycorpCanadaAndMolycorpSilmetMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_MolycorpCanadaMember" name="MolycorpCanadaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_MolycorpMember" name="MolycorpMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_MolycorpMountainPassFacilityMember" name="MolycorpMountainPassFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_MolycorpSilmetMember" name="MolycorpSilmetMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_MolymetMember" name="MolymetMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_NapaneeFacilityMember" name="NapaneeFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_NaturalgasdeliveryfacilityundercapitalleaseMember" name="NaturalgasdeliveryfacilityundercapitalleaseMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_NeoPowdersMember" name="NeoPowdersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_NetChangeInOperatingAssetsAndLiabilities" name="NetChangeInOperatingAssetsAndLiabilities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_NetChangeInOperatingAssetsAndLiabilitiesDisclosureTextBlock" name="NetChangeInOperatingAssetsAndLiabilitiesDisclosureTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_NetIncomeLossMember" name="NetIncomeLossMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_NoncashOrPartNoncashAcquisitionMiningRightsAcquired" name="NoncashOrPartNoncashAcquisitionMiningRightsAcquired" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_NoncashOrPartNoncashAcquisitionNoncashFinancialOrEquityInstrumentConsiderationSharesIssuedValue" name="NoncashOrPartNoncashAcquisitionNoncashFinancialOrEquityInstrumentConsiderationSharesIssuedValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_NonrecurringCosts" name="NonrecurringCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_NumberOfDaysToCalculateCommonStockPrice" name="NumberOfDaysToCalculateCommonStockPrice" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_NumberOfStockholderDerivativeLawsuits" name="NumberOfStockholderDerivativeLawsuits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_NumberofClassificationErrorsAffectingtheCondensedConsolidatingBalanceSheets" name="NumberofClassificationErrorsAffectingtheCondensedConsolidatingBalanceSheets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_NumberofClassificationErrorsAffectingtheCondensedConsolidatingStatementsofCashFlows" name="NumberofClassificationErrorsAffectingtheCondensedConsolidatingStatementsofCashFlows" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_OfferingPricePerShare" name="OfferingPricePerShare" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_OfferingPricePerShareUnderwriters" name="OfferingPricePerShareUnderwriters" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcp_OfficeSpaceTrailersAndEquipmentMember" name="OfficeSpaceTrailersAndEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_OfficersDirectorsAndOtherRelatedPartiesMember" name="OfficersDirectorsAndOtherRelatedPartiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_OperatingIncomeLossbeforeDepreciationAmortizationandAccretion" name="OperatingIncomeLossbeforeDepreciationAmortizationandAccretion" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_OperatingLeasesFutureMinimumPaymentsDueInYearsOneToThree" name="OperatingLeasesFutureMinimumPaymentsDueInYearsOneToThree" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcp_OtherAsiaMember" name="OtherAsiaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_OtherCountriesMember" name="OtherCountriesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_OtherequitymethodinvestmentsMember" name="OtherequitymethodinvestmentsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_OwnShareLendingArrangementSharesIssuedOfferedInRegisteredPublicOfferingPricePerShare" name="OwnShareLendingArrangementSharesIssuedOfferedInRegisteredPublicOfferingPricePerShare" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcp_OwnshareLendingArrangementMember" name="OwnshareLendingArrangementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_OwnshareLendingArrangementSharesMaximumSharesAllowed" name="OwnshareLendingArrangementSharesMaximumSharesAllowed" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcp_Parent12PercentTermLoanMember" name="Parent12PercentTermLoanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_PaymentsForNetIntercompanyAdvances" name="PaymentsForNetIntercompanyAdvances" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_PaymentsForProceedsFromBorrowingfromGuarantor" name="PaymentsForProceedsFromBorrowingfromGuarantor" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_PaymentsForProceedsFromBorrowingfromNonguarantor" name="PaymentsForProceedsFromBorrowingfromNonguarantor" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_PaymentsForProceedsFromBorrowingsFromParent" name="PaymentsForProceedsFromBorrowingsFromParent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_PaymentsForProceedsFromInvestmentInSubsidiaries" name="PaymentsForProceedsFromInvestmentInSubsidiaries" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_PaymentsForProceedsFromNotesReceivableFromGuarantor" name="PaymentsForProceedsFromNotesReceivableFromGuarantor" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_PaymentsForProceedsFromNotesReceivableToNonGuarantor" name="PaymentsForProceedsFromNotesReceivableToNonGuarantor" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_PaymentsForProceedsFromRepaymentsOfNotesReceivableFromGuarantor" name="PaymentsForProceedsFromRepaymentsOfNotesReceivableFromGuarantor" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_PaymentsForProceedsFromRepaymentsOfNotesReceivableFromNonGuarantor" name="PaymentsForProceedsFromRepaymentsOfNotesReceivableFromNonGuarantor" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_PaymentsForProceedsFromRepaymentsToParent" name="PaymentsForProceedsFromRepaymentsToParent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_PaymentsForProceedsFromSubsidiariesLoanRepayments" name="PaymentsForProceedsFromSubsidiariesLoanRepayments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_PaymentsToProceedsFromLoansToSubsidiaries" name="PaymentsToProceedsFromLoansToSubsidiaries" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_PaymentsToProceedsFromLoanstoGuarantor" name="PaymentsToProceedsFromLoanstoGuarantor" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_PennyWarrantsMember" name="PennyWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_PremiumPercentageAddedToCommonStockPrice" name="PremiumPercentageAddedToCommonStockPrice" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_PricePerShareOfCommonStockIssued" name="PricePerShareOfCommonStockIssued" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_PrimarySharesPurchasedByInsiders" name="PrimarySharesPurchasedByInsiders" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_ProceedsFromNetIntercompanyAdvances" name="ProceedsFromNetIntercompanyAdvances" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_ProceedsfromBorrowingfromGuarantor" name="ProceedsfromBorrowingfromGuarantor" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_ProductionCostsExpendedthatWouldHaveBeenAllocatedtoAdditionalTonsProduced" name="ProductionCostsExpendedthatWouldHaveBeenAllocatedtoAdditionalTonsProduced" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_PropertyPlantandEquipmentAdditionsGrossofCapitalizedInterest" name="PropertyPlantandEquipmentAdditionsGrossofCapitalizedInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_PurportedClassActionMember" name="PurportedClassActionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_QuarterlyFinancialDataLineItems" name="QuarterlyFinancialDataLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_QuarterlyFinancialDataTable" name="QuarterlyFinancialDataTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_RareEarthMetalsMember" name="RareEarthMetalsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_RareEarthQuotasMember" name="RareEarthQuotasMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_RareMetalsMember" name="RareMetalsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_ReclamationSuretyBonds" name="ReclamationSuretyBonds" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcp_RecognizedTransactionCosts" name="RecognizedTransactionCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_RedemptionPriceOfPrincipalAmount" name="RedemptionPriceOfPrincipalAmount" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_ReleaseOfInventoryStepUpValue" name="ReleaseOfInventoryStepUpValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_ResourcesMember" name="ResourcesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_RestrictedStockAwardsRestrictedStockUnitsAndPerformanceBasedRestrictedStockUnitsMember" name="RestrictedStockAwardsRestrictedStockUnitsAndPerformanceBasedRestrictedStockUnitsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_RevenueRecognitionSalesOfGoodsAndCostOfSalesPolicyTextBlockPolicyTextBlock" name="RevenueRecognitionSalesOfGoodsAndCostOfSalesPolicyTextBlockPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_ScheduleOfBusinessAcquisitionsTransactionCostsByTypeTableTextBlock" name="ScheduleOfBusinessAcquisitionsTransactionCostsByTypeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_ScheduleOfCondensedIncomeStatementAndComprehensiveIncomeTableTextBlock" name="ScheduleOfCondensedIncomeStatementAndComprehensiveIncomeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTable" name="ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_ScheduleOfInventoryCurrentAndNoncurrentTableTextBlock" name="ScheduleOfInventoryCurrentAndNoncurrentTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_ScheduleofChargestoCostofSalesBasedonNormalProductionLevelsandWriteDownofInventoryTableTextBlock" name="ScheduleofChargestoCostofSalesBasedonNormalProductionLevelsandWriteDownofInventoryTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_ScheduleofEquityandCostMethodInvestmentsTableLineItems" name="ScheduleofEquityandCostMethodInvestmentsTableLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_ScheduleofEquityandCostMethodInvestmentsTableTable" name="ScheduleofEquityandCostMethodInvestmentsTableTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_ScheduleofShareLendingArrangementsTableTextBlock" name="ScheduleofShareLendingArrangementsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_SchedulesofDepositsTableTextBlock" name="SchedulesofDepositsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPercentage" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_ShareBasedCompensationArrangementByShareBasedPaymentAwardMatchingContributionByEntityAsPercentageOfConvertedRestrictedStockUnits" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMatchingContributionByEntityAsPercentageOfConvertedRestrictedStockUnits" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcp_ShareExchangeAxis" name="ShareExchangeAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_ShareExchangeCompanyDomain" name="ShareExchangeCompanyDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_SharePurchaseAgreementMember" name="SharePurchaseAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsinPeriodWeightedAverageGrantDateFairValueTotal" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsinPeriodWeightedAverageGrantDateFairValueTotal" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcp_SharesIssuedDuringPeriodSharesNewIssuesPurchasedByRelatedParties" name="SharesIssuedDuringPeriodSharesNewIssuesPurchasedByRelatedParties" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_SharesIssuedDuringPeriodSharesNewIssuesUnderwriterFees" name="SharesIssuedDuringPeriodSharesNewIssuesUnderwriterFees" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mcp_SharesIssuedDuringPeriodSharesNewIssuesUnderwritersOptionToPurchaseWithin30Days" name="SharesIssuedDuringPeriodSharesNewIssuesUnderwritersOptionToPurchaseWithin30Days" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_SixPercentConvertibleSeniorNotesMember" name="SixPercentConvertibleSeniorNotesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_SpringingMaturityon12TermLoansMember" name="SpringingMaturityon12TermLoansMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_StockIssuedDuringPeriodSharesLoanedShares" name="StockIssuedDuringPeriodSharesLoanedShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_StockIssuedDuringPeriodSharesNewPrimaryIssues" name="StockIssuedDuringPeriodSharesNewPrimaryIssues" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_StockIssuedDuringPeriodValueLoanedShares" name="StockIssuedDuringPeriodValueLoanedShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mcp_StockIssuedDuringPeriodValueNewPrimaryIssues" name="StockIssuedDuringPeriodValueNewPrimaryIssues" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_StockpileMember" name="StockpileMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_StrikeWarrantsMember" name="StrikeWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_TaxCreditCarryforwardExpirationAxis" name="TaxCreditCarryforwardExpirationAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_TaxCreditCarryforwardExpirationDomain" name="TaxCreditCarryforwardExpirationDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_TenPercentSeniorSecuredNotesMember" name="TenPercentSeniorSecuredNotesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_TermLoan12PercentMember" name="TermLoan12PercentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_TermLoans12PercentandEquipmentFinancing12PercentMember" name="TermLoans12PercentandEquipmentFinancing12PercentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_ThreeAndQuarterConvertibleSeniorNotesMember" name="ThreeAndQuarterConvertibleSeniorNotesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_TodaMagnequenchMagneticMaterialsCoLtdMember" name="TodaMagnequenchMagneticMaterialsCoLtdMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_UnderwritingDiscountsAndCommissions" name="UnderwritingDiscountsAndCommissions" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_UnrecognizedTaxBenefitsTaxPositionRelatedToCurrentYearAbstract" name="UnrecognizedTaxBenefitsTaxPositionRelatedToCurrentYearAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcp_UnrecognizedTaxBenefitsTaxPositionRelatedToPriorYearsAbstract" name="UnrecognizedTaxBenefitsTaxPositionRelatedToPriorYearsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcp_UnrecordedUnconditionalPurchaseObligationDueInYearsFourAndFive" name="UnrecordedUnconditionalPurchaseObligationDueInYearsFourAndFive" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcp_UnrecordedUnconditionalPurchaseObligationDueInYearsOneToThree" name="UnrecordedUnconditionalPurchaseObligationDueInYearsOneToThree" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
</xsd:schema>


