Alloy – a metal made up of a mixture of two or more different metals. Common examples of alloys include bronze (a mixture of copper and tin), brass (copper and zinc), and pewter (tin with antimony, copper and sometimes lead).

Base Metal – non-precious metals used as a core for plating and gold-filled items. Brass and nickel are common base metals in jewelry.

Cabochon – a round or oval stone, cut and polished with one flat side (the back) and one smooth domed side (the front or face). A faceted cabochon is cut with faceted surfaces around the edge of the stone.

Chatoyancy (chatoyant) – having a changeable luster, like a cat’s eye.

Facet – a flat, polished surface cut into a stone or bead.

Finding – the catch-all term used to describe metal jewelry components. Clasps, connecting rings, the pins that hold the beads, ear wires and posts are all findings.

Gold – a yellow colored, soft, shiny metal commonly used in jewelry. The purity of gold is measured in “karats.” 24 karat (or 24k) denotes pure or fine gold; 12k is 50% gold; 14k is about 58% gold. Gold that is less than 24k is actually an alloy; the remaining percent of the material consisting of other metals, such as copper, silver and zinc.

Gold-filled – a thin layer of gold bonded to a base metal core. In gold-filled products, the gold layer must be at least 1/20th (5%) of the overall product, by weight. Any purity of gold may be used; most gold-filled products are made with either 12k or 14k gold. The purity of gold used can be determined by the notation in front of the words Gold-filled. 14/20 Gold-filled and 14k Gold-filled both refer to a gold-filled product in which 14k gold has been bonded to the base metal core. Likewise, 12/20 Gold-filled and 12k Gold-filled indicate that 12k gold has been

Gold-plated – a very thin layer of gold bonded to a base metal core. The layer of gold in Gold-plating is only required to be seven-millionths of an inch thick. (The layer of gold in gold-filled products is about one hundred times thicker than gold-plating.)

Opacity – the quality of not allowing light to pass through (the quality of being opaque).

Opaque – not allowing light to pass through; solid.

Sterling Silver – see Silver

Silver – a white colored, soft, shiny metal, commonly used in jewelry. Like gold, silver is available in different levels of purity: the purest form, Fine silver, is 99.9% silver; Sterling silver is 92.5% silver, with other metals (usually copper) making up the remaining 7.5%; Coin silver is 90% silver with 10% copper. Nickel silver is an alloy of copper (65%), nickel and zinc – no silver at all.

Silver-plated – a very thin layer of silver bonded to a base metal core.

Translucent – allowing some light to pass through; objects seen through translucent material are diffused or indistinct.

Transparent – easily seen through; allowing light to pass through without obscuring the ability to see objects on the other side.