Hardness of Nickel Vs. Palladium white gold

I am really hoping that someone can help me.

I have a ring that was made out of the Nickel white gold about 2
years ago. This ring had five 3mm high quality round emeralds set
along the top side of the ring in a straight line. This ring was done
by a custom jeweler. Not more than a month after having the ring, 2
of the stones fell out. Keep in mind that I am VERY delicate with the
ring. The jeweler replaced the stones and sent the ring back. After
another 6 months 2 more stones fell out of the ring. The ring has
since been re-cast in Palladium white gold. I am still VERY concerned
that the stones are going to fall out again.

Is there a significant difference between the hardness properties of
the Nickel and the Palladium white gold especially when using
emeralds??? Should I continue to worry about the stones falling
out? Could this be a problem with the jeweler that I chose to make
the ring?

I would greatly appreciate any on this matter!!! Thanks
in advance.

-Desiree

Desiree,

Often times when a stone or stones have fallen out of a ring, it is
the result of the stone having been broken in the setting and then
the pieces falling out. By the time you notice, the stone is gone.

I’m not saying that this is what happened in your case, but my
suspicions are always heightened when emeralds are involved. Even
with very careful wear these stones–especially something with a
profile like a cabachon-- can get knocked around. With something as
generally brittle as an emerald, it doesn’t take much to nail the
stone.

In my experience, nickel whites tend to be harder than palladium
whites. That being said, the palladium acts a bit like fine gold in
that it compresses on itself or is pushed from one area to another
rather than wear away. In a palladium white gold alloy however,
I’ve seen considerable wear on bezels and on ring sides. I think that
the higher palladium whites-- those alloys containing more palladium
in the alloying material-- this “burnish vs abrade” effect might play
a bigger role.

Hope this helps,
Andy Cooperman

Is there a significant difference between the hardness properties
of the Nickel and the Palladium white gold especially when using
emeralds???  Should I continue to worry about the stones falling
out?  Could this be a problem with the jeweler that I chose to
make the ring? 

Nickel-based white gold alloys are susceptible to “stress corrosion”
cracking, predominately in prongs that are naturally under tension
to hold the gemstone in place. Everyday chemicals in the environment,
such as chlorine in swimming pools, dishwashing soaps, etc…will
induce this chemical reaction, resulting in prong failure and
potential loss of As a general rule, the higher the nickel
content, the more susceptible the alloy is to stress corrosion.
Nickel white gold alloys also have a greater hardness than palladium
white alloys as a general rule.

Palladium-based white gold alloys (and platinum alloys) are
resistant to stress corrosion cracking, but are generally more
expensive than nickel white gold alloys. Stuller carries a wide
variety of white gold casting alloys, ranging from low nickel to high
nickel and low to high palladium contents. Palladium white gold is a
good choice for white gold prong applications. Hope this helps answer
your questions.

James Gilbert
Stuller Metals
800-877-7777

Hello,

I can help with this one…

Nickel white is really a hard metal. Your note made no mention of
the setting method, I’m presuming either tiny prong like a bright
cut or a bezel setting deal down in the metal, burnished in. With
Emeralds there will be a minimum of metal pushed against the stone to
keep it in place given the nickel alloys natural hardness. With
palladium having a soft nature you can gently push more metal around
to secure the stone. More metal may very well work out to more
durability IF the client is not abusing the item.

This is all said sight unseen of course, so it sure could be the
jeweler. Funny how a softer ally can give a jeweler the working
properties to do a more durable job. I’d love to see a close up
picture of the ring…

Daniel Ballard

Desiree,

Nickel white gold is very hard. It is very difficult to set emeralds
in it without breaking them. Palladium white golds are much softer
and I suspect the setter would be able to make the settings much
tighter without risking damage to the stones.

Steve Brixner
www.brixnerdesign.com

Hoover & Strong was the first company to do the benchmark testing on
the effects of chlorine, etc. on nickel based alloys. You can read
the article here; I think you will find it interesting:

Stewart Grice, also of Hoover & Strong has written a very
informative article on different white alloys:

Eugene C. Gentile (Gino)
National Accounts Manager
Hoover & Strong, Inc.
295 Princeton-Hightstown Road
Unit 11-364
West Windsor, NJ 08550

877-687-7770
Fax: 609-936-1838

EGentile@hooverandstrong.com

Desiree,

Inspection by another jeweller is a good idea. Stones of any kind
which are set by a person with professional training should not fall
out of settings. At worst, they may become loose over time, but not
leave the settings.

In my experience, it is seldom a materials issue. I have repaired
other people’s settings for a generation, and it has become
strikingly obvious that there are some wonderful craftsmen and women
out there who are self-taught in setting. Proper technique is rare.

If stone breakage due to rough wear were really the culprit, the
damage would be evident on the remaining stones as well. It doesn’t
sound like this is the case.

A loupe reveals accuracy in bearing-cutting. Thickly-girdled stones,
such as round emeralds or sapphires with bulbous pavillions, require
careful attention to the depth and height of the bearing, and
appropriate thickness of the material used. A good setter should be
able to create an accurate bearing in ANY material, including steel,
with minimal risk of breakage.

I’m so sorry that this has happened to you. Dissapointment in a
custom piece doesn’t sell much more jewellery down the road, nor
does it lend credibility to any jewellers, period.

Take the time to find an expert, and have the problem sorted out, so
that you may wear the piece and enjoy it without fear.

David Keeling
www.davidkeelingjewellery.com