The J-STD-006C-AM1 amendment provides better detail of a solder alloy's maximum allowed deviation about the nominal level of the element's mass than was provided in past alloy standards. The J-STD-006C-AM1 amendment provides information on negative effects of adding rare earth elements to specific, heavy tin-containing, lead-free solder alloys and propensity of tin whisker formation. Finally, the J-STD-006C-AM1 amendment inserted five new, patented lead-free solder alloys from 3 separate alloy suppliers for users of the J-STD-006C standard.