ASTM International Standard Specification for Refined Silver ASTM B413-26

This specification deals with refined silver cast bar form in three different grades as indicated by the degree of fineness of silver: Grade 99.90 (UNS P07020) which is also commonly referred to as commercial bar or bullion; Grade 99.95 (UNS P07015); and Grade 99.99 (UNS P07010). The material shall be produced by any process and shall conform to the chemical composition requirements for silver, copper, bismuth, iron, lead, palladium, selenium, and tellurium as shall be determined by any destructive or nondestructive method of chemical analysis. The bar shall be cast with a brand and shall be marked with the minimum fineness together with the melt number, bar number, and weight for identification.