Abstract: Novel 22 k gold alloys including silver, boron, cobalt and copper. The alloys meet modem jewelry fabrication techniques requirements and exhibit pleasing yellow color. They are stable under normal use and do not appreciably tarnish. They also have substantially no discoloring effect on the skin. These formulations possess work hardening properties consistent with gold alloys of lower karat while maintaining color properties consistent with traditional 22 k gold jewelry.

Abstract: An indium-free, gold-colored, tarnish and corrosion-resistant alloy having no greater than 10% by weight gold and a color value, as measured according to the Cielab Color Measurement System, of approximately L=87.4, a=1.1, b=15.3. The alloy comprises 28-35% copper, 19.5-22.5% silver, 6-11% palladium, 22-32% zinc, 0.1-1% aluminum, and 0.5-3% platinum.

Abstract: A gold based alloy containing gold, silver, copper, zinc, silicon, iron, boron, nickel and indium for the manufacture of gold articles is described which has a lower melting point, extended remelting capabilities, high resistance to cracking, improved color consistency and increased ductility.

Abstract: A strip of silver-copper brazing alloy, connected to the positive terminal of a rectifier, is passed through an acid treatment bath containing a cathode adjacent each face of the strip. The strip is resistively heated to a temperature of at least 350.degree. C. prior to its entry into the treatment bath by passing an electric current through the strip and the treatment bath to the cathodes. Copper oxide is electrolytically dissolved from the surface of the strip in the treatment bath.

Abstract: A method for recovering high grade gold alloy in an unoxidized condition from karat gold clad to a base metal substrate without significant oxidation of the substrate, wherein the substrate is employed as an anode in an aqueous solution of from about 0.02 to about 2% by weight nitric acid and is subjected to electrolysis at a temperature of from about 48.degree. C. to about 94.degree. C. for sufficient time to delaminate karat gold from the substrate in particulate form and deposit same in the solution, from which the delaminated karat gold may be separated.