Hello Everyone!
I have two questions regarding rhodium plating; 1. Let’s say for
example you’re sizing a ring that is white gold and when you are
polishing it you start to see patches of rhodium wearing away. Is it
neccesarry to remove ALL of the old rhodium plating from the piece
BEFORE you can re-plate it?
- What is the best way to remove old rhodium plating? It seems like
I polish forever and ever and the old rhodium will not come off, are
there any tricks I am unaware of?
Also, I have noticed a bit of a pitting problem with white gold
prong re-tips. Any advice out there on how to remedy this problem. I
hate having prongs that look like swiss cheese.
Any advice would be very much appreciated.
Sincerely,
Belinda
Hi Belinda,
You don’t have to remove all the rhodium before replating but you do
need to polish the whole piece. It’s best to replate a uniform
surface so I try to get it all off the flat surfaces…(sometimes
you might need to sand paper it)…prongs I stay way from.
As for retipping…Too soft of a solder will pit easily on prong
tips. Try using a harder solder or solder a piece of wire to the old
prong and cut off the excess…then refinish…
Hope that helps,
Mark
There is no shortcut to removing rhodium. It is harder than gold or
platinum, and using any acid or chemical would dissolve all of the
base metal before the rhodium is even touched. If you heat the piece
it can disintigrate the plating - I’ve read the details of that, but I
forget them, now. It requires a fairly high heat, too. Mostly you’re
better off sanding and polishing it away. You’ll get best results by
removing it all, but if the surface is smoothly polished it should be
fine. We’ll size a white ring, polish only the shank and replate and
you can’t tell.
Retipping: You are boiling your solder. You are putting the solder on
top of the prong and trying to heat through the solder to the prong.
Put the solder on top, and heat the prong from the side until the
solder just slumps and “grabs” the prong. This is one reason why hard
solder is best, because easy solder will get watery much quicker and
go splat. You can fix it by steaming it (get the polish out of the
pits), reflux and reflow.
http://www.donivanandmaggiora.com
There is no shortcut to removing rhodium. It is harder than gold
or platinum, and using any acid or chemical would dissolve all of
the base metal before the rhodium is even touched.
Ok then, here’s a question I’ve wondered about for a while. My
wedding set is 14k white gold and it was rhodium plated originally.
Over the past 21 years (geez, has it been that long already? Doesn’t
feel like it!) the plating has worn off so the rings have a lovely
antique-ish color to them. For our 20th anniversary, DH bought me a
white gold and diamond ring wrap, also rhodium plated. It looked
really bad next to the wedding set because of the difference in the
metal colors.I really prefer the look of the natural white gold to the
rhodium… I took the new ring to a local jeweler to have it sized down
(I don’t work with gold and I didn’t want to start learning with my
new ring). While I was there, I asked if he could do something about
the rhodium plating. I got it back, sized and stripped of rhodium the
very next day. It looks great, and now it matches the wedding set. If
rhodium is so hard to remove, how did he get it off?
Kathy Johnson
Feathered Gems Jewelry
Just a question, What happens if you invert the polarity of the
electrodes, could then the Rodium get back to the solution, I know
some guys which chrome old bumpers and once they told me that this
was the way to recover the chromiun.
Teeh
I asked if he could do something about the rhodium plating. I
got it back, sized and stripped of rhodium the very next day. It
looks great, and now it matches the wedding set. If rhodium is so
hard to remove, how did he get it off?
Kathy, rhodium is hard to remove chemically, because it’s more inert
than the metals it’s usually applied over. it sometimes can be
stripped, especially in cases where the rhodium is applied over a
nickel underplate, since the nickle layer can be chemically attacked
without attacking the base gold or silver, or the rhodium, which then
flakes off the rhodium layer. Still nasty to do, thus the prior
comments on removing rhodium.
But that doesn’t mean you can’t just buff it off. It is indeed
harder than the underlying metals likely are, but it’s on top, after
all, fully exposed to any buffing operation… All your jeweler did
was a good thorough buffing of the ring to remove the rhodium.
Especially platinum polishing compounds, which are hard enough
abrasives to quickly cut platinum or rhodium or other harder metals,
the rhodium comes off quickly and easily. The hard part is getting
out of recessed areas you cannot reach with a buff, should you need
to be this thorough…
cheers
Peter Rowe
Hi,
I got it back, sized and stripped of rhodium the very next day. It
looks great, and now it matches the wedding set. If rhodium is so
hard to remove, how did he get it off?
I think you were lucky to find that both of your rings are made from
a closely matched (colour etc) 14ct w/g alloy. They could have easily
looked a lot different.
To answer your question:
Your jeweler would have needed to file the area that was soldered or
hammered, then emery a slightly wider area before polishing. You
said you didn’t want the rhodium so he would have repolished the
whole ring. I assume there is no sign of any rhodium left so the
plating was probably not very thick and depending on the alloy a
quick buff might have taken most of it off. There may be some
residual areas that have plating still on them, but the areas where
the buff cant reach are usually hard to see and underexposed areas
don’t electroplate well, esp.’ in 14k.
I have never had to go past polishing the rhodium off. The most
inert alloys like platinum and fine gold are not affected by
sulphuric acid so for them it would be easy enough to reverse the
polarity (strip) the outlying layer and what happens then depends on
the other alloys in the mix. I suspect cyanide stripping would work
in this case, but I don’t know.
Platinum group alloys are the key.
I see which alloys: take rhodium the best, which can be dipped for
longer, which need extra attention etc, and I have found that any
fraction of platinum group metals (platinum/palladium etc) help a
lot.
Cheers,
Phillip
Rhodium is possibly the most precious metal:
It is the whitest platinum group alloy. It is less inert then
platinum.
Electroplated, it is hard (but scratchy - a long term problem for
exposed unmatched metals).
It is much more expensive then platinum. Diamonds love it.
&, It binds best with platinum group metals.
www.platinumsmith.com.au
Hi Friends,
Can you tell me a way to easily remove a rhodium plating from a
sterling charm? I have a customer who wants to me oxidize a sterling
charm to match the rest of their charm bracelet, and unfortunately
the charm has been rhodium dipped. I steel-wooled it, but there are
just tons of crevices etc. that I can’t reach and of course those
areas need to take the Black Max.
Ideas?
Bonnie
Bonnie Alvarez
Owner, Birth Designs
Hi - the best way is to get is stripped - ie reverse electroplated.
Assuming you don’t have the facilities yourself, you can get this
done cheaply by anybody who offers a rhodium plating service.
Best wishes
Harriet (UK)