Back to Ganoksin | FAQ | Contact

Copper less sterling silver casting alloy


#1

Hello All:

Is there such a thing as copper less sterling silver that is just as
hard as sterling silver? A friend of mine - another jewelry was
telling me that Tiffany has always used a copperless alloy for
sterling silver that is not deox silver and is just as hard as
regular sterling and does not tarnish as easily as regular sterling.
If this is true, where can you get this magic alloy from?? I heard of
Tiffany Gold alloy from a caster in NYC but never Tiffany Silver
alloy.

DeDe


#2

Never seen it, despite some research. Tyler Teague, any ideas for
this person?

Daniel Ballard


#3

Hi Dede,

I have a theory about why Tiffany Sterling does not seem to tarnish
as quickly as other sterling jewelry.

I think the main reason is that people tend to keep their Tiffany
jewelry in the Tiffany box and in the blue felt pouch. It could be
that the box is made from low sulphur paper or perhaps the felt is
treated in someway (perhaps like Pacific cloth?). Even if the box or
the felt are not treated, just keeping the sterling jewelry in a box
and in felt would lower the amount of air circulation and humidity
that causes unprotected pieces to tarnish faster. It also could be
that Tiffany may treat the piece with something like 3m’s Tarnishield
that will help prevent tarnishing for a while.

People are proud to own a piece made by Tiffany and the box and
pouch are rarely discarded. They are kept and used. Other sterling
jewelry does not have the “cachet” and tends to be kept unprotected.

I have a pair of Tiffany cufflinks that I’ve kept unprotected on top
of my dresser (in a tray along with my loose change!) for a month and
they have tarnished as badly as the “off brand” sterling chains I
keep in the same tray.

Dan T.

PS. I’ve discovered that you should never wash a poodle with Suave
Dandruff control shampoo… He smells HORRIBLE.


#4

Hi DeDe,

With all due respect, to me, some (much) of this sounds "iffy."
Saying Tiffany has always done something is a pretty long stretch.
How would someone, other than a Tiffany historian, know that? That
they wouldn’t have evolved in their materials and practices in 100
years seems unlikely to me. “Umbrella” statements like that always
make me suspicious.

As our friend Al in Australia has pointed out, the silver/copper
alloy is the traditional definition. How long have these non-copper
alloys even been around? I would make an assumption that at least in
the first half of the century, Tiffany was using the traditional
alloy.

I don’t believe Tiffany does its own casting… or at least not all
of it. I know a caster (possibly lurking here) who tells me he has
done a significant amount of casting of Tiffany work while in the
employ of a casting house. I suppose the company (Tiffany) could
specify the alloy to be used by a contract casting company. If he
doesn’t respond to this question himself, I’ll inquire offline for
some feedback.

If the alloy is resistant to tarnish, as compared to the
copper/silver alloy, doesn’t that make it de-ox? I supposed we need
to define the term “de-ox”, but to me it has meant an alloy with a
reduced or eliminated copper content to minimize susceptibility to
tarnish. If not, what is the definition of de-ox you folks are using
that would eliminate this magical Tiffany alloy from the category?

I wouldn’t spend too much effort trying to track down a rumor, if
that’s what it is.

All the best,

Dave

Dave Sebaste
Sebaste Studio and
Carolina Artisans’ Gallery
Charlotte, NC (USA)
dave@sebaste.com


#5
 Copper less sterling silver casting alloy Is there such a thing as
copper less sterling silver that is just as hard as sterling
silver? 

Sure I used to use a 92.5% fine silver with 6.75% zinc mixture which
is fairly standard in Gujarat nad Rajastan and I and most like
thinking minds on this board consider it to be called “sterling
silver”… I felt like it was pretty similiar in hardness to the
copper mix…


#6

sorry Tiffany and Co. does use copper in their 925 silver, that is
why alot of their 1837 rings have tarnish on them and turn peoples
fingers green, it discontinues after a week or two because the copper
in the silver disapates and poses no further problem.

Aaron A Tracy
used to work for Tiffany and Co in the service dept


#7
    Never seen it, despite some research. Tyler Teague, any ideas
for this person? 

Hey Daniel, I did quite an extensive development project on tarnish
resistant sterling silver alloys along with a buddy of mine. The
Vicker’s hardness of standard silver/copper sterling (as cast) is
about 141. There are some deox sterling alloys that contain no
copper but they are all soft alloys comparatively and start in the
(as cast) state from around 75 - 90 Vicker’s. It was my conclusion
at the end of the project that while some additives can increase the
hardness of a soft deox sterling alloy, any reduction in the amount
of copper in the alloy adversely affects hardness. At the same time
I must also say that while there are alloys that can be heat treated
to increase the hardness to nearly the hardness of a standard (925 Ag
/ 75 Cu) alloy, nearly, is the key term.

So to answer the question, sure there are alloys that contain no
copper and you can make one yourself easily enough. Are they as hard
as standard sterling silver? No, not in the (as cast) state. It is
unlikely that an alloy for a deox sterling that contains no copper
can be heat treated to the hardness that can be obtained with
standard sterling. It is a matter of interstitials. Interstitial
solid solutions occur when the solute atoms occupy the interstices
(spaces), between the solvent atoms. At least two factors come into
play here. It is the size of the solute and solvent atoms and the
dispersion in the interstices. It is the stress on the crystal
lattice caused by these “impurities” that add hardness. If the atoms
of the additions to silver fit nicely and neatly into the
interstices between the silver atoms then they cause little stress
and the resulting alloy will be soft. The Copper atom is larger than
say, Zinc so it causes distortions in the lattice and thereby causes
stress which is turn causes hardness.

The last thing I would like to address is the thing with Tiffany’s
silver. Tiffany is a great company that has certainly done an
incredible job of marketing it’s name and their products are
typically made of high quality materials and have great workmanship.
This does not however mean that any of the products that any of you
out there make are any less. Tiffany is a name brand just like
Salamander crucibles, or Levi jeans. Their alloy person gets up in
the morning and puts on their protective gear just like the rest of
us. We are all governed by the laws of nature, no more, no less.

Hey, it’s about 6:00am here and I haven’t had a cup of coffee yet.
Maybe Mr. Jim Binion can correct me if I am wrong or answer some more
on this if your interested. I must have caffeine now.

Best Regards,
J. Tyler Teague


#8

Dear Tyler, Thanks for an excellent essay on the properties of
sterling silver vs. de-ox silver.

On a practical level it is apparent that some of the finished
jewelry that is coming in from foreign sources utilizes the softer
silver that results from using less copper. It is also apparent that
as a result of the softness of said silver, heavier wear components
are the standard. For example, the ring shanks are typically much
heavier that those used in sterling rings. Obviously the makers are
keen to making the metal more workable in spite of using a bit more
metal.

As for the Tiffany marketing ploys, brand name strategies are
typically a way of squeezing more profit from a product that isn’t
necessarily any better than generic merchandise. Recently one of my
customers came in with a sterling French rope bracelet which had
lost some links. She wanted me to solder some new links where the
old had gone missing. I pointed out to her that since none of the
other links had ever been soldered it might be a situation of
spending good money after bad. She was incredulous pointing out the
fact that there was a tiny tag appended to the bracelet stating that
it had come from Tiffany and that she had paid a handsome sum for
it.( She had actually purchased it from Tiffany in NYC ) There may
have been a time when brand names were synonymous with quality.
Unfortunately nowadays brand names can just as easily be cheap crap
that is over priced ! One of the better examples of cheap
merchandise being masqueraded under the guise of quality brand
naming are quartz watches. I can think of several overpriced watch
brands that sell for many times more than their no name equivalents.
Ron at Mills Gem, Los Osos, CA


#9

Hey Tyler, Had to respond since you were kind of talking about me.
While I do not personally make the alloy, I am the metallurgist and
do oversee the process to some extent. I agree with your kind words
about us. We are about workmanship and quality however we are not
gods. Sterling silver will tarnish no matter who makes it. Different
people will react differently to different alloys. We have had
various customers tell us that they are sensitive to just about
every metal found in standard jewelry alloys. One customer even told
us they were allergic to platinum and wanted an engagement ring made
of white gold! Go figure. Internally we use the standard plain
vanilla sterling composition that we set the standard for many moons
ago. We have yet to be swayed by the tarnish resisitant (don’t call
it anti tarnish cause it isn’t) silvers out there. They come with
their own set of headaches. Making alloys is always about
compromise. You boost one property at the expense of another. Have I
gotten off track? Sorry. Now it’s time for my coffee.

Tino Volpe
Metallurgist, Technical Manager
Tiffany & Co.
300 Maple Ridge Drive
Cumberland, RI 02864-8707
401-288-0124