1、Designation:B56295(Reapproved 2012)Standard Specification forRefined Gold1This standard is issued under the fixed designation B562;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 indi
2、cates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers refined gold in cast bar form(Note 1).1.1.1 Grade 99.5Gold having a minimum fineness of 995.1.1.2 Grade 99.95Gold having a minimum fineness
3、 of999.5.1.1.3 Grade 99.99Gold having a minimum fineness of999.9.1.1.4 Grade 99.995Gold having a minimum fineness of999.95.NOTE1Other forms of unfabricated gold of commerce are not to beexcluded under this specification.1.2 The values stated in inch-pound units are to be regardedas standard.The valu
4、es given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 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 become
5、familiarwith all hazards including those identified in the appropriateMaterial Safety Data Sheet(MSDS)for this product/materialas provided by the manufacturer,to establish appropriatesafety and health practices,and determine the applicability ofregulatory limitations prior to use.2.Referenced Docume
6、nts2.1 ASTM Standards:2E29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE1446 Test Method for Chemical Analysis of Refined Goldby Direct Current Plasma Emission Spectrometry3.Materials and Manufacture3.1 The metal may be produced by any process that y
7、ields aproduct capable of meeting the requirements of this specifica-tion.The purchaser,upon request,shall be informed of therefining process used.3.2 The bars shall be of a quality generally acceptable to thetrade.4.Chemical Composition4.1 The refined gold shall conform to the chemical compo-sition
8、 prescribed in Table 1.NOTE2For purposes of determining conformance with thisspecification,an observed value obtained from analysis shall be roundedto the nearest unit in the last right-hand place of figures used in expressingthe limiting value,in accordance with the rounding method of PracticeE29.5
9、.Sampling5.1 On agreement between the manufacturer and thepurchaser,a sample may be taken from the melt before pouring(Note 3).The sample shall be in the form of shot or pins(Note4 and Note 5).NOTE3A single melt or bar(s)cast from a single melt shall constitutea lot for sampling.NOTE4Pins of38in.(9.
10、5 mm)or other suitable diameter may be castinto graphite molds or drawn into evacuated glass tubes.In some cases itmay be necessary to draw the glass tube pins through 60-grit emery paperbefore acid leaching to remove adhering glass particles.NOTE5In order to avoid surface contamination,the sample,i
11、rrespec-tive of its nature,is to be leached in hot 1+1 HCl for 5 min,washed inwater,rinsed twice in alcohol or acetone,and dried in a muffle at 110Cbefore portions are taken for analysis.5.2 On agreement between manufacturer and purchaser analternative sampling procedure may be used.5.3 The amount o
12、f sample taken shall be sufficient to supplythree portions for analysis;the mass of each portion shall besufficient to permit the determination of its composition as setforth in Table 1.5.4 After mixing thoroughly,the sample shall be dividedinto three parts,each placed in a package and sealed;one fo
13、rthe manufacturer,one for the purchaser,and one for theumpire.5.5 All tools required are to be reserved exclusively for thiswork.1This specification is under the jurisdiction of ASTM Committee B02 onNonferrous Metals and Alloys and is the direct responsibility of SubcommitteeB02.05 on Precious Metal
14、s and Electrical Contact Materials.Current edition approved Nov.1,2012.Published November 2012.Originallyapproved in 1972.Last previous edition approved in 2005 as B562 95(2005).DOI:10.1520/B0562-95R12.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service
15、 at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.Method of Analysis6.1 Chemical composition of the ma
16、terials set forth in thisspecification shall be determined,in case of disagreement,inaccordance with Test Method E1446.The selection of testmethods for the determination of elements not covered by thattest method shall be a matter of agreement between themanufacturer and the purchaser.6.2 Chemical composition of materials required for Grade99.5 refined gold shall be determined by a test method similarto the fire assay test method listed in the appendix.7.Rejection and Rehearing7.1 Rejection:7.1.
