Glossary

Alloy: A metal composed of two or more elements, usually obtained by fusing a mixture of metals.

Base Metal: A term used to describe common metals as distinct from precious metals. The term "base metal" covers steel, copper, brass, zinc, tin, lead, nickel and many others.

Coin Silver: An alloy of 90% silver and 10% copper.

Composite Metal: A material made of two or more different metals bonded together, usually in layers.

Double Plate: A silver coating having an average thickness twice that of "Standard Plate."

dwt: An abbreviation for pennyweight, one pennyweight equalling 1/20 troy ounce or 24 grams.

German Silver: See nickel silver.

GF: An abbreviation for Gold Filled. Gold: A metallic element.

Gold Filled: A composite material of base metal coated on one or more sides with karat gold alloy. For jewelry, other than watch cases, the proportion of karat gold is required to be at least 5% of the weight of the composite metal. For watch cases the karat gold coating is required to be at least 0.003 in. thick.

Irid: An abbreviation for iridium.

Iridium: A metallic element and one of the six platinum metals.

Iridium-Platinum: An alloy of iridium and platinum. A common composition is 10% iridium and 90% platinum.

Irid Plat: An abbreviation for iridium-platinum.
Jewelry Palladium: A term used to describe an alloy of 95.5% palladium and 4.5% ruthenium.

K: An abbreviation for karat.

Karat: 1/24 part by weight of the metallic element gold - see Karat Gold.

Karat Gold: A gold alloy. For 10, 14, and 18 karat golds, the nominal content of pure gold is respectively 10/24, 14/24, and 18/24 or 41 % %, 58% % and 75% of the alloy, meas-