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Ted Mooney, P.E. RET
Pine Beach, NJ
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for Metal Finishing since 1989
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Brass plated silver turns black
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Q. I have a question of brass plating on silver jewellery and after silver plating is possible or not?
Which plating on silver jewellery does not oxidize.
- Rajkot Gujarat
August 21, 2022
A. Hi Pujan
Brass plating on silver plating is possible, but we appended your query to a thread where a potential problem with it is explained.
The best plating on top of silver, and a very conventional one, is probably rhodium.
Luck & Regards,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
A. Brass over silver and/or rhodium over silver and/or anything else, with time (weeks) will allow the silver to diffuse thru to the top and corrode. You must have a "barrier" like palladium or nickel between.
Robert H Probert
Robert H Probert Technical Services
Garner, North Carolina
August 21, 2022
A. Thanks for the clarification, Robert.
I wasn't suggesting Rhodium between silver and brass plating; to be clear I was answering Pujan's other question of "Which plating on silver jewellery does not oxidize?".
Luck & Regards,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
⇩ Related postings, oldest first ⇩
Brass plated silver turns black
Q. I have a brass plating process on silver, with potassium bichromate passivation afterwards.
My problem is that brass plated article after 15 days become of a black shade.
What can I do?
- Surat, Gujrat, India
May 31, 2012
A. Hi,
The cause of the blacking is almost certainly due to migration of silver into the brass coating. We see the problem more commonly with silver plating on brass or copper. The remedy would be a thicker coating of brass or to use a nickel undercoat.
I am very curious as to why you are plating inexpensive brass onto silver. Would you mind explaining?
Harry Parkes
- Birmingham, UK
I am brass plating on silver with potassium bichromate solution because it gives rich golden color without using gold.
- Surat, Gujrat, India
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