Designation:D4373−21StandardTestMethodforRapidDeterminationofCarbonateContentofSoils1ThisstandardisissuedunderthefixeddesignationD4373;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thistestmethodcoversthedeterminationofcarbonatecontentofsoilsandsoftrockwhichcanbereadilybrokendownbymechanicaleffort.Itisagasometricmethodthatusesasimpleportableapparatus.Resultsshouldbeclearlystatedasthecalciteequivalentinpercentbecausedifferentcarbonatespeciescoverawiderangeofpercentcalciteequivalentasshownbelowforanumberofcarbonates:SpeciesCationCalciteEquivalent,%MagnesiteMg117.0DolomiteCa,Mg108.6CalciteCa100.0AragoniteCa100.0RhodocrositeMn87.1SideriteFe86.4SmithsoniteZn79.8WitheriteBa50.7CerrusitePb37.5Forexample,a100%dolomitewouldbeexpectedtoyield108.6%calciteequivalentwhile100%sideritewouldyieldonly86.4%calciteequivalent.Calciteandaragonitereactionswilltypicallycompletewithinabout10minutes.Thismethoddoesnotdistinguishbetweenthecarbonatespeciesandsuchdeterminationmustbemadeusingquantitativechemicalanaly-sismethodssuchasatomicabsorption.1.2Units—ThevaluesstatedinSIunitsaretoberegardedasstandard.Thevaluesgiveninparenthesesareprovidedforinformationonlyandarenotconsideredstandard.ReportingoftestresultsinunitsotherthanSIshallnotberegardedasnonconformancewiththisstandard1.3AllobservedandcalculatedvaluesshallconformtotheguidelinesforsignificantdigitsandroundingestablishedinPracticeD6026.1.3.1Theproceduresusedtospecifyhowdataarecollected/recordedorcalculated,inthisstandardareregardedastheindustrystandard.Inaddition,theyarerepresentativeofthesignificantdigitsthatgenerallyshouldberetained.Theproce-duresuseddonotconsidermaterialvariation,purposeforobtainingthedata,specialpurposestudies,oranyconsider-ationsfortheuser’sobjectives;anditiscommonpracticetoincreaseorreducesi...
