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Metal Plating and Filling:
What you see is not necessarily
what you get--less expensive metals can be superficially transformed by the
application of another type of metal onto the original's surface.
This is not plating, but is a method by which the mold of the jewelry piece
is electrically coated with layers of gold. The mold is then removed,
leaving only the gold. Electroformed jewelry has a "big look" because
it is hollow--the process is suitable mainly for pins, brooches and pendants
which are not subject to rough handling, since the gold is very thin (about
.003-.007 in.) and can be easily dented.
Gold Filled (GF): A
process by which a relatively thick layer of gold is mechanically applied to
a base metal and fused by heat and pressure. The layer must be at least
10K gold and 5% of the total weight of the item. Gold Overlay and
Rolled Gold Plate is the same as GF, except only 2.5% of the item must be
Gold Electroplated (GEP):
A layer of gold at least 7mils (7/1,000,000 of an inch) thick is electrically
deposited onto the base metal by immersion in a liquid containing chemically
bound gold molecules. Gold Flashed or Gold Washed is the
same as GEP, except the gold is less than 7mils thick. Except for our
24K Rose, ViridianGold.com does not sell GEP items--however, some jewelry items
may have plated accents in contrasting gold color.
Ion Plating: A process by which
atomic-sized ion particles of metal are deposited via an electric beam onto
another metal. Depending on the type of metal used for the ions, different colors
may be plated.
Jewelry items may be plated with Palladium, rather than Rhodium (below), to
enhance whiteness, since Palladium is also a naturally white, platinum-group
metal, and much less expensive than rhodium.
Rhodium Plated: Rhodium
is a member of the Platinum family of metals--it is actually whiter and harder
than platinum. Rhodium is used to plate most white gold in order to give
it a more durable finish and a whiter color and sometimes is used to plate sterling
silver to resist tarnishing (when sterling silver is plated with rhodium, it
should not be polished for this will eventually remove the rhodium's protective
effect). Some yellow gold jewelry items may have rhodium-plated accents.
Rhodium is very expensive, about five times the cost of platinum.
Pronounced "vair-may", it is sterling silver which has been plated
or rolled with genuine gold. If a gold-colored item is marked "925" or
"STER", that usually indicates that it is vermeil.
Metal Type / Weight:
Gold is the most popular
metal for fine jewelry today, with platinum gaining in popularity. Other metals
such as sterling silver, stainless steel and titanium are also used in fine jewelry.
At ViridianGold.com, the weight
of a jewelry piece refers to its gold content.
Therefore, a 14K diamond ring specified as having a weight of 4.4 grams indicates
that the ring is composed of 4.4 grams of 14K gold, exclusive of the weight of the
stones. For rings that we offer in different stock sizes, the weight given
in the product description is for the standard stock size of 6 for women's rings
and 10 for men's rings. When comparing gold or platinum jewelry, always note
the weight of the piece rather than its size dimensions, since two pieces that are
similar in appearance may have significantly different gold content, and hence value.
See our helper page for weight and size comparisons
of U.S. Coins
is too soft in its pure state to be used for most kinds of jewelry. Pure
gold is specified as 24K, where "K" is the abbreviation for karat, a
measure of purity (not to be confused with carat,
a measure of weight). In order for gold to be usable for jewelry, it must
be mixed with other metals to form an alloy which is stronger than gold in its
pure form. So, 14K gold is 14/24 pure, or about 58.5% gold and 41.5% other
metals--copper is used in both yellow and white gold, with silver being added
for yellow gold and nickel for white gold. 14K gold is thus stronger than
18K gold, and yet retains the bright color indicative of gold, even though it
is less costly and contains less pure gold than 18K does. White gold is usually
also plated with rhodium, which is a platinum-group metal, in order to enhance
its whiteness. Often, yellow gold is selectively plated with rhodium to
form a two-tone color scheme, such as a yellow gold setting with the setting
prongs of the diamond plated with rhodium. Gold is also specified by
fineness, where a fineness of 1000 indicates 100% purity. 14K gold
thus has a fineness of 585, and this number is often stamped on jewelry instead
of the karat mark; 10K gold has a fineness of 417 (41.7% gold). In order
to be called "gold" in the US, the metal must be at least 10K. To learn
more about gold, its standards and mining, go to the
World Gold Council website.
Palladium: This white, platinum-group
metal is quickly growing in popularity now that new alloys allow for quality
casting while maintaining 95% purity, and many are predicting that it will replace
white gold as the white metal choice for jewelry. Palladium is similar
in hardness to 14K white gold, and is thus harder than platinum. In addition,
it is 44% less dense than platinum, and costs much less per ounce--thus, jewelry
made with palladium is much less costly. Like platinum, it does not require
alloying for whiteness, and thus it is naturally hypoallergenic (contains no
nickel). Palladium is about 1/3 the cost (per gram) of platinum.
For more information about palladium, its characteristics and how it is mined,
go to the
StillWater Palladium website.
Prior to the 1940's, platinum was popular in engagement and wedding rings, but
it was outlawed for non-military use at the outbreak of World War II.
White gold was substituted, and remained popular even after the war because
of its lower cost and easier fabrication--however, in the last 15 years platinum
has increased in popularity. Pure platinum, unlike pure gold, is structurally
strong, partly because it has a higher density and melting point, a characteristic
which makes it more difficult for jewelers to work with--however, platinum is
softer than 14K white gold and therefore scratches more easily. Because
of its natural properties, platinum jewelry need not be as highly alloyed as
gold--platinum jewelry with a fineness of at least 950 (95% Platinum) may be marked simply
as "Plat." or "Pt.", but if the fineness is less, the piece must be marked to
indicate this, such as "900 Plat. (90% Platinum)." Note that all platinum jewelry sold by ViridianGold.com is 950 fineness and will be marked thusly. The alloy most commonly used for the other 5% in our jewelry is Ruthenium. Since platinum is true white, it
does not require rhodium plating as white gold does, and is naturally hypoallergenic (it does not contain
nickel). For more information about platinum, consult the
Platinum Association website.
Sterling Silver: Silver
is the whitest of all jewelry metals. Like gold, silver is too soft to
use for jewelry in its pure state, so it is usually found as Sterling Silver,
an alloy of 92.5% silver and 7.5% other metals, usually copper. Items
marked with "SS" or "925" are sterling silver. Sterling silver will tarnish,
of course, but when manufactured as highly polished, sterling silver will need
little if any polishing when worn as jewelry.
Sometimes silver is plated with rhodium to prevent
tarnishing (and if so, it should not be polished for this will remove the rhodium's
protective effect), or with gold to produce a type of metal called
vermeil. We will always tell you in the specifications
if a silver jewelry item is rhodium plated. For more information about
silver, go to the
Black Silver: A black, naturally-occurring
silver ore which is 68.8% silver, combined with antimony and sulfur.
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