Gold electroplating solution can be purchased online at CaswellPlating.com and at DalmarPlating.com as of 2015. Both websites sell acid-based, cyanide-free 24-carat gold plating solution with cobalt added to increase durability.
24-carat gold electroplates directly onto copper, brass, silver and other metals. Some alloys require copper or nickel plating before they can be electroplated with gold. Steel must be nickel plated first. Variations in the color of electroplated gold are achieved by controlling the voltage used during the electroplating process.
Caswell Plating sells 24-carat gold tank-plating solution in pint, quart, gallon and 2-gallon containers. Dalmar Plating sells 24-carat gold plating solution in quart, gallon and 5-gallon containers.