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  <xsd:element id="uslm_NetIncomeLossPercentage" name="NetIncomeLossPercentage" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="uslm_RevenueAbstract" name="RevenueAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="uslm_RevenuesPercentage" name="RevenuesPercentage" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="uslm_ShippingAndHandlingRevenues" name="ShippingAndHandlingRevenues" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="uslm_LesseeOperatingLeaseSupplementalCashFlowInformationTableTextBlock" name="LesseeOperatingLeaseSupplementalCashFlowInformationTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="uslm_LesseeLeasingArrangementsOperatingLeasesRenewalTerms" name="LesseeLeasingArrangementsOperatingLeasesRenewalTerms" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="uslm_LesseeOperatingLeaseLiabilityPaymentsDueYearFiveAndAfterYearFive" name="LesseeOperatingLeaseLiabilityPaymentsDueYearFiveAndAfterYearFive" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element name="EarningsPerSharesBasicAndDilutedAbstract" id="uslm_EarningsPerSharesBasicAndDilutedAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FuelEnergyAndTransportationCosts" id="uslm_FuelEnergyAndTransportationCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PersonnelExpenses" id="uslm_PersonnelExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="O2026Q1DividendsMember" id="uslm_O2026Q1DividendsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="O2026Q2DividendsMember" id="uslm_O2026Q2DividendsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="O2026Q3DividendsMember" id="uslm_O2026Q3DividendsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
</xsd:schema>
