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How to make cyanide-free gold brush plating solution?

Hi, my name is Mike I have just started in brush-plating, as it seems to be taking off here in the UK although I know it has been around for many years in USA,I have recently found out that there is a cyanide free gold plating solution and knowing this is much safer to make I wondered if any one can tell me how to do it? I have a few gold items I presume I will have to dissolve them some how to make a solution.

Thanks,

Mike Osborn
brush plater - United Kingdom
2007

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First of two simultaneous responses -- 2007

Mike
Brush plating has been widely used in the UK for many, many years. It has been applied to repairing ship's propeller shafts and microcircuits. During this time the process has been developed by professional chemists with deep knowledge of plating. For minor applications, we just take some solution from the plating tank. For serious work we all buy the proprietary process.
To explain why, start with your spare gold. First you need to dissolve it. Not many chemicals dissolve gold. You are in practice limited to cyanide (which you probably cannot buy) and aqua regia, a mixture of hydrochloric and nitric acids which is a very nasty brew. Unless your gold was 24 carat, you then need to purify it before you get started on the real chemistry.
I suggest that your best (simplest and safest)option is to trade in your scrap gold to a specialist supplier and ask for payment in brush plating solution.
Good luck

Geoff Smith
Hampshire, England

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Second of two simultaneous responses --

Try www.uspto.gov website-there you can find some expired patents for cyanide free gold plating solutions (one thiosulphate based, and one tartrate based ...). Very good book on brush plating by M.Rubinstein [Electrochemical Metallizing] can help you too (but without any formulas).Hope it helps and good luck!

Goran Budija
- Cerovski vrh Croatia
2007

I need to know how to make Gold brush plating solution formula, I know that PGC in brush more concentrate than tank, but how about another chemical concentrate? Please advise how to make brush gold plating solution in 100 ml.

Ali Shodiqin
hobbyist - Indonesia
August 17, 2011