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- I can't get a straight
answer! Is all gold yellow or not? Gold is an
element and it is yellow; there are no isotopes of gold
that are white or any other color. Therefore pure
24 kt gold is always yellow. But jewelry is never made
from 24 kt gold anyway because it is far too soft to be
usable.
- What color is "jewelry gold"
then? Gold jewelry is made from an alloy of
gold plus other metals. 12 kt gold, for example, is
12/24ths gold and 12/24ths other metals. The color of the
alloy will depend on what those other metals are, and in
what proportion. If the other metals are copper and
silver, the jewelry will be yellow.
- What exactly is "white gold"
then? 12 karat white gold would be half gold
and half other metals, including palladium and/or nickel.
These metals have a bleaching effect so that the mixture
will be whitish. Nickel is much cheaper than palladium,
so nickel is widely used in white gold jewelry in the
U.S.; but so many people are allergic to nickel that it
is forbidden in jewelry in Europe, and palladium would be
used there instead.
- What is rhodium and what
does it have to do with white gold jewelry?
Now it gets interesting! Rhodium is a precious
metal more than ten times as costly as gold. Rhodium is
not a feasible material to make solid jewelry from
because it is too stressed and brittle. But rhodium is
great as a thin plating for jewelry because it is
glitteringly, dazzlingly, white and mirror-like. Nothing
sets off diamonds like rhodium plating does. But it is
only a plating and therefore it will wear off after some
period of time and require replating.
- Have things changed between
your grandmother's white gold ring and yours?
Yes! Years ago, white gold rings were not rhodium plated;
today they usually are. Which is better and why? Well, if
you feel that heirlooms should not require replating, you
won't be happy with a rhodium plated ring because it
will. But if you love today's brilliant, dazzling,
ultra-white diamond-like look, you simply can't get it
from an unplated ring, and you never could. No matter how
well it's made, an alloy which is about half yellow gold
can never even come close to offering the flashy glint of
rhodium plating. Yes, your grandmother's ring lasted
decades and never needed plating, but it was never
glittery and dazzling like today's rings -- it was white
enough for her taste in a different time.
- Where's the part where it
starts to really suck? Right here! If today's
rings were like your grandmother's ring except with a
layer of rhodium plated onto them, few people would be
unhappy. If you wanted it to knock your eye out you'd get
it replated frequently; and if a more antique look
pleased you, and you object to replating heirlooms, you'd
just let the plating wear off or ask the jeweler not to
plate it.
But most of today's rings are not of the same alloy as
your grandmother's! Once the jewelers recognized that
"it's going to be rhodium plated anyway" they talked
themselves into accepting that the underlying metal
didn't need to be the pleasing shade of your
grandmother's ring. White gold is graded by color, i.e.,
whether it's white enough to be left unplated -- and most
of today's white gold isn't (if interested, see the
article White Gold Alloys: Colour Measurement and
Grading at
www.goldbulletin.org/downloads/Henderson_2_38.pdf which
explains this whiteness factor). In fact, jewelry stores
in the center aisle of malls apparently sometimes rhodium
plate yellow gold rings, and the contrast as they start
to wear is terrible!
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