The authoritative public forum
  for Metal Finishing since 1989
-----

Electroplating Gold with Gold Anodes

I am looking for electrolytes and plating processes that use gold as the sacrificial/soluble anode to supply Au. All Gold Electroplating information I've seen is for acid or cyanide gold supplies and inert anodes.

Bruce R. Kay
- Tolland, Connecticut, USA
2006

---

Using, and keeping on hand, anodes that cost over $400 per ounce has surely hampered interest in this technology, Bruce, so I'm not aware of any such baths. I don't see a reason conventional gold baths could not work with a mix of gold anodes and inert anodes though. But maybe mixing anodes defeats your objective--which is why we request that posters please explain what they are trying to do instead of framing the inquiry in the abstract. Why do you want to use gold anodes please?

P.S.: In looking at "Gold Plating Technology" by Reid and Goldie .

while working on another matter today, I did see mention of this, and they noted that additional free cyanide must be added. Sorry, I don't know offhand how much detail on this topic is in that volume.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006

---

Last time I saw this type of application was about 30 yrs. ago in No. Attleboro, Ma. The application was gold electroplating( more of flashing ) brass jewelry(mostly chain)Gold color is controlled by time & voltage w/o agitation and the amount of free cyanide.

Usually the gold anode(24K) is rolled into very thin sheets. The Electrolyte are made 4 oz. per gal of Sodium Cyanide and 2.0z per gal of Sodium Hydroxide. The solution is charge by making the gold anodic and copper is made cathodic inside a porous cup whose pores are smaller than the gold ions. Basically you are making a double salts of Potassium Gold Cyanide(mixture Of Au+1 & Au+3). The concentration of the gold in the electrolyte is dependent on the amount of current and time you use (Faraday's Law).

You are better off buying the gold salts from a supply house.

Hamilton Solidum
- Mays Landing, New Jersey
2006