I’ve been sizing and doing a minor soldering repair on a 14K Rose Gold ring and the color of the whole piece has turned a very brassy yellow. This has happened before with rose gold, but not every time that I work with it. I can’t figure out what I’m doing differently to cause this change. I’ve heated the ring with lots of flux several times and tumbled and the color seems to have faded significantly (though it’s not entirely back to normal). Has anyone experienced this? Any help would be much appreciated!
Sounds to me like fire scale. You will need to polish it a little deeper to remove it.
Not firescale - depletion gilding. Rose gold is a copper heavy alloy, the
pickle dissolves the copper from the surface and leaves a thin layer of
yellow gold. Just have to scrape that off with a rubber wheel, sandpaper, a
little heavier polish, etc. Tumbling is just going to burnish the yellow
layer down, you’ve got to remove it.
–Willis
I often purposefully cultivate a depletion guided surface on rose gold. I love what I think of as the apricot color. Only on items and in areas that will not receive high wear.
Please excuse any typos-- curse my clumsy digits…
I like that color too. Hoover and Strong sells a Peach gold, sort of in between yellow and rose.
Mark
Good luck with dissolving copper in pickle.
One of the reasons why copper tongs are used to get objects out of the
pickle.
Another reason is that copper tongs do not contaminate the pickle as steel
or iron tongs will do.
Pickle only dissolves copperoxide, fluxes AND iron or steel.
I’m sorry to disagree with you Willis.
Best regards
Best regards
Sorry, yes, the copper in the top layer oxidizes with heat. That copper
oxide is what dissolves in the pickle to create the depletion gilding
effect.
Good firecoat helps prevent the oxidation, but it’s hard to be perfect.
That’s why accidental depletion gilding is usually splotchy instead of even
across the piece. Uneven flux, or maybe a hot spot where the flux burns
off, lets more copper oxide form on the surface.
Thanks for catching that
What ever we call it the answer is the same. If you don’t like it you have to sand it off and re-polish. And thats a sad thing if it is going to take off details that are important to you.
Thank you all for your help! This is my first time posting here and I’m really grateful for all of the responses. It sounds like depletion gilding is the answer and unfortunately there’s no good solution for this piece- too detailed and too many crevices to polish out, though I did remove a lot of the color from the exposed surface. In the future, a better and more even flux will help prevent this?
Yes it will , I would use Boracic Acid mixed with Metho {Two teaspoon to a cup} kept in a screwtop jar , Dip & light it {After the lid is back on} praps a few times, for a nice dusting !
Okay will do. Thank you for the advice, much appreciated!
Careful with that stuff. I have personal put out two jewelers who were going up in flames because they spilled it while holding a lit torch. It was funny but only after they were doused with a dry chemical extinguisher.
Gives a new meaning to the term “fire coat”
yikes! I will be very careful!
Fire is not the only danger. Methanol is also toxic. Vapor and skin contact can cause toxicity. Naturally we use it in small amounts so if you spill on the skin, wash off immediately and should be no harm but… Wear Gloves and have good ventilation.