ASTM_E_2295_-_13.pdf

Designation:E229513Standard Practice forFire Assay Silver Corrections in Analysis of Metal BearingOres,Concentrates,and Related Metallurgical Materials bySilver Determination in Slags and Cupels1This standard is issued under the fixed designation E2295;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice covers the determination of silver correc-tions for fire assay of metal bearing ores,concentrates andrelated metallurgical materials using the spent slags and cupelsfrom the fire assay process,by gravimetry and atomic absorp-tion spectrophotometry.1.2 The test methods appear in the following order:SectionsGravimetric Method1011Atomic Absorption Method12131.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.(See Practices E50and ISO Guide 35:1989.)2.Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE50 Practices for Apparatus,Reagents,and Safety Consid-erations for Chemical Analysis of Metals,Ores,andRelated MaterialsE135 Terminology Relating to Analytical Chemistry forMetals,Ores,and Related MaterialsE882 Guide for Accountability and Quality Control in theChemical Analysis LaboratoryE1024 Guide for Chemical Analysis of Metals and MetalBearing Ores by Flame Atomic Absorption Spectropho-tometry(Withdrawn 2004)3E1335 Test Methods for Determination of Gold in Bullionby Fire Assay Cupellation Analysis2.2 ISO Documents:4ISO Guide 35:1989 Certification of Reference MaterialsGeneral and Statistical PrinciplesISO 10378:1994 CopperSulfideConcentratesDetermination of Gold and Silver ContentsFire AssayGravimetric and Atomic Absorption SpectrometricMethod3.Terminology3.1 DefinitionsFor definitions of terms used in thispractice,refer to Terminology E135.4.Summary of Practice4.1 In the process of fire assay fusion slags and cupels arecollected,retreated and silver is determined in them to providea correction value for the fire assay determination of silver(seeGuide E1024,Test Methods E1335,ISO 10378:1994,Bugbee,5and Smith6).5.Significance and Use5.1 These methods are primarily intended to be used for thedetermination of silver correction in the fire assay silverdetermination.Silver assays are determined by fire assay forthe purpose of metallurgical exchange between seller andbuyer.1This practice is under the jurisdiction of ASTM Committee E01 on AnalyticalChemistry for Metals,Ores,and Related Materials and is the direct responsibility ofSubcommittee E01.02 on Ores,Concentrates,and Related Metallurgical Materials.Current edition approved Nov.1,2013.Published December 2013.Originallyapproved in 2003.Last previous edition approved in 2008 as E2295 03(Reap-proved 2008)1.DOI:10.1520/E2295-13.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from International Organization for Standardization(ISO),1,ch.dela Voie-Creuse,Case postale 56,CH-1211,Geneva 20,Switzerland,http:/www.iso.ch.5Bugbee,E.E.,A Textbook of Fire Assaying,Third Ed.,John Wiley and Sons,Inc.,Hoboken,NJ,1946.6Smith,E.A.,The Sampling and Assay of the Precious Metals,Second Ed.,Charles Griffin and Co.,Ltd.,1947.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.2 It is assumed that all who use this method will be trainedanalysts capable of performing skillfully and safely.It isexpected that work will be performed in a properly equippedlaboratory under appropriate quality control practices such asthose described in Guide E882.6.Apparatus6.1 Analytical Balance,capable of weighing to 0.01 g.6.2 Analytical Balance,capable of weighing to 0.001 mg.6.3 Assay Furnace,capable of temperatures up to 1100 C,accurate to 6 5 C.6.4 Atomic Absorption Spectrophotometry,AAS.6.5 Ring Grinder,250 g capacity.7.Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests.Unless otherwise indicated,it is intended thatall reagents conform to the specifications of the Committee onAnalytical Reagents of the American Chemical Society wheresuch specifications are available.7Other grades may be used,pr