Metal finishing Q&As since 1989

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Carbon in gold plate

February 25, 2010

Hi
George here,
I'm interested in introducing carbon into a gold plating process, is this possible?

Thank You

George Hope
hobbyist - Attleboro, Massachusetts, USA

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Hi, George. Anything is possible. The devil is in the details. What are you trying to accomplish?

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
February 26, 2010

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February 28, 2010

George

All gold deposited from the usual GPC bath contains some carbon in the form of a co-deposited cyanide polymer. This adds some lubricity to the deposit and is part of the reason why electroplated gold has a density of about 17.5 g/c rather than the 'book' density of 19.3 g/cc. Which also explains why thickness/wt calculations are often misleading and lead to endless arguments with inspectors and buyers.

But - if you want lumps of elemental carbon in the deposit, you probably only have to create a suspension of carbon in the plating solution. Don't expect to get a smoooth deposit tho. Getting the particle size etc right may not be easy and gold solutions are expensive to play with.

But, as Ted says, if you tell us what you are trying to achieve, you might get more helpful answers

Good luck

Geoff Smith
Hampshire, England