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  <xs:element id="mnts_ShareBasedPaymentArrangementOptionsUnderStockIncentivePlanMember" abstract="true" name="ShareBasedPaymentArrangementOptionsUnderStockIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ProceedsFromIssuanceOfFinancialInstrumentsSubjectToMandatoryRedemption" abstract="false" name="ProceedsFromIssuanceOfFinancialInstrumentsSubjectToMandatoryRedemption" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_PreferredStockPurchaseWarrantsMember" abstract="true" name="PreferredStockPurchaseWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_StableRoadAcquisitionCorporationAndAffiliatesMember" abstract="true" name="StableRoadAcquisitionCorporationAndAffiliatesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_May222021StockOptionModificationsMember" abstract="true" name="May222021StockOptionModificationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
