Rhodium plating with diamonds in situ

Hi, A member of the public has just approached me with a query that
one of you, I’m sure, can answer.

It seems that her platinum engagement ring was re-rhodium plated and
now her diamond looks much more yellow.

I would guess (from past experience) that because her ring look
whiter and brighter, the diamond looks less so in comparison.

But -

(a) is it usual and safe practice to rhodium plate jewellery with
the diamonds in place

and

(b) is there any possibility that colour or quality of diamonds
could be affected (the only thing I can think of is if fissur fillers
in diamonds were disolved out or if laser drillings were filled - any
thoughts?)

Thanks
Jack Ogden

Jack,…that same person wrote to me, but her email address didn’t
work, drats! “Fracture Filled” could be the answer, the oil “leached
out”…why did they Rhodium plate on a Platinum ring. was it covering
up something? they had a yellow band soldered onto the Plat., could
they have not used a Laser…??? Platinum has its own personal
colouring… so there is no reason to plate it…??? It is very 100%
safe to Rhodium plate with the diamonds already set in! I think the
original jeweller missed a few spots on her ring, I might add ! lots
of my setting IS plated…Gerry!

Hello Jack: Bright rhodium plating will make a yellowish stones
appear more yellow.

There is a range of yellow stones that are better looking set in
yellow prongs as it draws away some of the color and fancy yellow
stones are often set in yellow prongs to enhance the color. The only
reason I can see to rhodium plate platinum is if some repairs were
done and white gold solder was used or maybe they sized it with lower
melt point platinum solder and wanted to cover up the line it left.
Is she sure it’s the same stone? Rhodium plating is completely safe
for diamonds and will not plate them or change their color. I am not
sure if Blue diamonds can be plated as they are electrically
conductive. Hope this helps.

Michael R. Mathews, Sr.

The first question coming to mind on this is why is anyone rhodium
plating a platinum ring? The only reason to rhodium plate something
is to make it look whiter but platinum is already a pretty pure
white. So probably she had a white gold ring that had yellowed as
the plating wore off and then probably, yes, it just looks yellowier
against the now whiter background. Plating should not have altered
the diamond in any way. Even if it did effect a fracture filled
stone (unlikely) that wouldn’t make the stone look any different in
color as fracture filling pretty much only effects the amount of
visible inclusions in the stone.

Daniel R. Spirer, GG Spirer Somes
Jewelers 1794 Massachusetts Ave Cambridge,
MA 02140 617-491-6000
@spirersomes
www.spirersomes.com

Just a thought: Perhaps they wanted a higher shine finish than
platinum provides…after all platinum is a little gray… Ringman

Thanks for all the comments. It is my understanding the rhodium
plating of platinum jewellery is not that uncommon - it hides solder
seams and adds a nice hard white surface to some of those modern
platinum/cobalt alloys used for casting that are not as hard as folk
expect platinum to be.

What happens if you try to rhodium plate a piece of jewellery set
with an electroconductively blue diamond … Intriguing thought.
Also some Moissonite’s are electroconductive.

Jack

I dispute that platinum is a “little” gray or a “little” grey or
that it is gray (grey) at all. I have a disc of all of the current
platinum alloys used in the US including Plat/S+ 1 & 2. each disc has
one half highly polished and the other half is a matte finish applied
via bead blasting. The grey association is base on the low
reflectivity of the matte finish and not the polished "high"
reflectivity.

I put this set of Pt disks together to dispute people who make
claims that Pt/Co is "blueish or Pt/Ru is “greyish”. I have found
that no one can pick between these disc and tell which is which.

Chris

As far as platinum alloys are concerned 95% platinum 5% cobalt is
the hardest as cast alloy (135 HV). With exception the patented
Plat/S+ alloys by Steven Kretchmer which range between 135 HV to 200
HV.

Rhodium plating platinum is a waste of money, unless it is a cover
up for solder joints or discoloration by other impurities. Don’t go
throwing good money after bad!

Chris

Chris: Have you ever seen perfection last? If it is not worn then yes
you can achieve a high finish, But what happens if it is worn? of
coarse it gets abraded and isn’t polishing platinum fun? Try holding
it to the shine silver produces and it will indeed be a different
tone. to each their own… Ringman John Henry

Yes, John, silver is whiter than platinum as rhodium is also.
However, wear and tear will occur regardless if it is plated or not
when worn frequently. It is the nature of the beast. You will have to
replate it repeatedly over a life time.

Chris