Gold plating rubs off easily

Hello everybody,

I had some silver medallions/tags cast for making engraved
bracelets, and then had some of them rhodium plated and others gold
plated (18k I was told).

I had read somewhere that the plating should be 3 microns thick to
be lasting but I don’t know of any way to measure the layer after the

So I started rubbing one of the gold plated medallions with a silver
cleaning cloth, and the plating came off in 15-20 seconds! Is that
normal? Obviously you shouldn’t clean a plated medallion with that
kind of cloth, but still… I did the same thing with a gold plated
brass medallion I had bought and it didn’t rub off.

  1. How can obtain a better plating quality?

  2. I know it depends mainly on 2 factors: the amount of gold in the
    bath, and the duration of the bath. What is the quantity and duration
    required to get a plating that is at least 1 micron thick?

  3. Is there any way to test the quality of the plating?

  4. I noticed some small marks on the plating and was told that it
    could be due to bubbles in the plating. Is there such a thing?

  5. The are also some cloud-like marks on some of the pieces, any
    idea what could have caused that?

  6. Will applying some kind of coating over the plating increase it’s

  7. Is it stupid to try and gold plate silver medals? Would gold
    plating brass produce much better and longer lasting results? (I
    consider brass jewelry as junk personally…)

  8. What nickel free alloy is best suited as an underplate for gold
    plating silver (in order to avoid having the silver show when the
    yellow gold plating wears off)

I really hope someone will be able to help me,
Thanks a lot