American Society for Testing and Materials (ASTM). Current edition approved June 1, 2006. Published June 2006. Originally approved in 1985. Last previous edition approved in 2000 as B 742 – 90 (2000). 3 p. This specification covers fine silver grade 99.9 % in fabricated form. The forms covered are tubing, rod, wire, strip, and sheet for electrical contact applications.