All About Jewels: GOLD
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Illustrated Dictionary of Jewelry
Click on an underlined word for more information on that subject.
The one dollar US Sacajawea coin.
Although it appears to be made of gold, it is not!
It is an alloy of copper, zinc, manganese, and nickel.
Gold is a precious metal that has been valued by people since ancient times.
People use gold for coins, jewelry, ornaments, and many industrial purposes.
Until recently, gold reserves formed the basis of world monetary systems.
Gold is a very soft metal when it is pure (24 Kt. is pure gold).
Gold is the most
(hammerable) and
(able to be made into wire) metal.
Gold is usually
(mixed with other metals, often silver and ) to make it less expensive and harder.
The scientific abbreviation of gold is Au.
The purity of gold jewelry is measured in .
Some countries hallmark gold with a three-digit number that indicates the parts per thousand of gold. In this system, "750" means 750/1000 gold (equal to 18K); "500" means 500/1000 gold (equal to 12K).
Percent Gold
58.3% Gold
Alloyed gold comes in many colors:
Colored Gold
Alloy Metal(s) Added to the Gold
Yellow Gold
50% silver and 50% copper
White Gold
Nickel, zinc, copper, tin and manganese
Pink (rose) Gold
90% copper and 10% silver
Green Gold
High proportion of silver or cadmium
15-20% iron
A Glossary of Gold-Related Terms:
AQUA REGIAAqua regia is a 3:1 mixture of hydrochloric acid and nitric acid.
Aqua regia i it is one of the few substances that can dissolve gold and platinum.
ASSAYAn assay is a test of the purity of an alloy.
A tiny piece of metal is scraped from the piece and the percentage of
or silver is determined.
Official assay offices determine whether a piece qualifies for an appropriate .
BLACK HILLS GOLDBlack Hills gold is
jewelry that is made (but not always mined) in the Black Hills area of South Dakota, USA.
The first gold found in that part of South Dakota was about 1874, discovered by Horatio N. Ross.
E.O Lampinen opened the Black Hills Jewelry Manufacturing Company in Deadwood, South Dakota in the early 1900's.
Modern day Black Hills jewelry often has a three-color (,
and ) grape leaf and vine pattern.
There are many companies that make Black Hills jewelry today, but by law, their creations must be made from Black Hills gold.
This jewelry is often (but not always) 10 Karat gold.
BLUE GOLDBlue gold
with a bluish tinge. It has been
with a mix that includes iron.
CHENIERChenier is fine, hollow tubing that is used in the production of some jewelry findings (like clasps and joints), and lately, in the actual production of jewelry.
The hollow tubes are lightweight and save in the use of gold.
The tubes are hard to bend when they are empty, so a metal rod is inserted before bending, facilitating the bending.
DUCTILEA ductile substance is easily pulled or stretched into a thin wire.
is the most ductile metal.
ELECTROPLATEElectroplating (also called Galvanotechnics after its inventor, Luigi Galvani) is a process in which one metal is coated with another metal using electricity.
In jewelry, inexpensive metals are frequently electroplated with more expensive metals, like
(gold plating),
(electrocoppering), rhodium (rhodanizing),
(chromium plating), or
(silver plating).
The thickness of the metal coat varies.
Electrogilded coating is the thinnest (less than 0.000007 inches thick); gold-cased metals have a coating thicker that 0.000007 inches.
ELECTRUMElectrum is an amber-colored alloy of
that was was used in ancient times.
Electrum is also an alloy used in medieval times consisting of
(50%), nickel (30%) and zinc (20%).
FINENESSFineness is the proportion of silver or gold in a metal alloy.
Fineness is usually expressed in parts per thousand.
For example, the fineness of
FOOL'S GOLDFool's gold is pyrite, a shiny, metallic mineral that looks like gold, but is actually a a form of iron.
stones come from pyrite.
GOLD DOREGold dor& (pronounced gold doh-rey) is a bar of semi-purified gold (e.g. bullion).
After being mined, the first stage in the purification process of the gold ore produces a cast bar (gold dore) that is approximately 90% gold.
The other 10% is mostly metals like silver and copper.
GOLD FILLEDGold filled (abbreviated G.F. or written as "doubl& d'or") jewelry is made of a thin outer layer of gold atop a .
For example, jewelry marked 1/20 G.F. 12 Kt. is at least 1/20th gold and is layered with 12
To be classified as gold-filled, a piece must be at least 1/20 gold by weight.
GOLD PLATEDGold-plated metal has a very thin layer of gold on the surface, usually applied by the process of electroplating.
Pieces that are gold plated are often marked G.E.P., gold electroplate, gold plated, or electro-plaqu& d'or.
GOLD STONEGoldstone (also known as ) is a shimmering
stone that ranges in color from yellow to red to light green to light brown.
The shimmer is caused by tiny metallic particles (mica) within the stone (not gold).
GREEN GOLDGreen gold is
that has been
with a higher percentage of
GREY GOLDGrey gold is
that has been
with 15-20% iron.
HALLMARKA hallmark is an official mark (or a series of marks) made in metal that indicates the fineness of the metal and the manufacturer's mark.
For example,
a hallmark of 925 indicates 925 parts of gold per 1000 weight.
Other hallmarks indicate the maker of the piece and sometimes the year of manufacture.
In many countries (like Britain) it is illegal to hallma some countries are notoriously lax in their enforcement of hallmark honesty.
Percent Gold
58.3% Gold
KARATKarat (abbreviated Kt) is a measure of the fineness of .
24 karat gold is pure gold.
18 karat gold is 18/24 gold (about 75% gold - three quarters gold).
14 karat gold is 14/24 gold (about 58% gold - a little over half gold).
12 karat gold is exactly half gold. 10 karat gold is 10/24 gold (only about 43.5% gold - less than half gold).
KARATCLADKaratclad is a trademark for a very this type of plating is about 14 times thicker than standard electroplating.
LEAFMetallic leaf is paper-thin sheets of metals.
For example, , , , and
are rolled or pounded into metallic leaf which can be applied to surfaces.
MALLEABLEMalleable metals are easily worked with a hammer or a roller.
are very malleable metals.
NOBLE METALSThe noble metals are gold, platinum, and silver.
These are metals that are relatively impervious to chemical action.
PINCHBECKPinchbeck (also known as "false gold") is a
that looks like .
Pinchbeck was invented by the British watchmaker Christopher Pinchbeck () in the early 18th century.
Pinchbeck consists of 83% copper and 17% zinc.
Ironically, there have been many imitations of Pinchbeck (which itself is an imitation).
PINK GOLDPink gold (also known as rose gold) is
with a tinge of pink. It has been
with a mix of 90%
PLATINGPlating or electroplating (also called Galvanotechnics after its inventor, Luigi Galvani) is a process in which one metal is coated with another metal using electricity.
In jewelry, inexpensive metals are frequently electroplated with more expensive metals, like
(gold plating),
(electrocoppering), rhodium (rhodanizing),
(chromium plating), or
(silver plating).
The thickness of the metal coat varies.
Electrogilded coating is the thinnest (less than 0.000007 inches thick); gold-cased metals have a coating thicker that 0.000007 inches.
PYRITEPyrite (also known as fool's gold) is a shiny, metallic mineral that is a form of .
stones come from pyrite.
ROLLED GOLDRolled gold is a very thin sheet of
that is laminated to a lesser metal (usually brass).
The two layers of metal are heated under pressure to fuse them together.
The sheet is them rolled into a very thin sheet and then used to make jewelry or other objects.
Jewelry made from rolled gold wear well over time.
Rolled gold pieces are marked rolled gold plate, R.G.P., or plaqu& d'or lamin&.
ROSE GOLDRose gold (also known as pink gold) is
with a pink tinge. It has been
with a mix of 90%
RUSSIAN GOLD FINISHA Russian gold finish is a matte, antique-look finish.
jewelry often has a Russian gold (plated) finish.
Equivalence
1 pennyweight
24 grains = 1.5552 grams
1 Troy ounce = 20 pennyweight
31.1035 grams
1 Troy pound = 12 Troy ounces
TROY WEIGHTPrecious metals (like gold, platinum, and silver) are measured in troy weight, which has units of pennyweights, ounces, and pounds.
Troy ounces and pounds are different from everyday US measures.
VERMEILVermeil is gold-plated silver.
Less occasionally, gold-plated bronze is referred to as vermeil.
dragonfly pin above is gold-plate over silver.
WHITE GOLDWhite gold is
that has been
with a mix of nickel, zinc, copper, tin, and manganese.
YELLOW GOLDYellow gold is
that has been
with a mix of 50%
YGFYGF is an abbreviation for yellow gold filled.
Illustrated Dictionary of Jewelry
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If the jewelry term you are looking for is not in the dictionary, please
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