Show properties of gold pure gold Is unaffected unaffected a by the atmosphere cither either at ordinary temperatures or when the metal is heated it Is 1 also proof against the action of common acids when used singly moreover it confers its properties more or less upon copper and silver when these medals are alloyed with it thus for or example twelve karat gold will withstand the action of nitric acid and tho the atmosphere at ordinary temperature but some of the copper will be oxidized during annealing alne ine parts of V gold may be alloyed with ten parts of 0 f platinum in an ordinary crucible and fire but such an alloy will not be uniform A larger larger proportion of platinum will free itself from the gold on uon tion and a homogeneous alloy of the two metals cannot be obtained jewelers circular weekly h b |