Jewelry Terms

There are many stone shapes and cuts. Learn about different kinds.


Jewelry Terms & Definitions

Sometimes the terms used in the jewelry industry can seem as clear as mud. I’ll try to clear up the mud as much as I can here. These are terms and definitions put as simply as I can figure out how without losing their meaning.

Carat – A carat is a measure of weight. It’s not the same as a karat. A carat is 1/5 of a gram in weight.

Designer Cabochon (Designer Cab) – A cabochon with an unusual but defined shape, such as teardrop, shield, bullet or others. The stone in the pendant in the photo is a designer cabochon.

Dichoric glass was originally created for the space and laser industries, and was developed extensively by NASA. The word dichroic means “two colors” because of the two or more colors that the glass reflects and transmits. Because of its fascinating beauty, dichroic glass is used extensively today by glass artists and jewelry artists as cabochons and other shaped art glass.

Doublet (Dublette) – Is a gemstone made of two layers. The two layers of stone are permanently bonded together either for a special look or for durability. Some stones are commonly sold as doublets, such as charoite, because charoite is fragile and splits easily, so it is backed with a harder stone like agate to make it more durable.

Faceted – A faceted stone has small, flat-cut surfaces that make a sparkling effect on transparent stones, although translucent and even sometimes opaque stones are faceted. Traditionally, diamonds, rubies and sapphires are faceted to show off their brillance. 

Four C’s – These are the factors that determine the value of a diamond or other gemstone. They are cut, clarity, color, and carat weight. Cut is how well the piece is shaped; clarity is how clear it is; color is how valuable a color it is; and carat weight is the weight of the stone.

Freeform Cabochon (Freeform Cab) – A cabochon with a free, undefined shape. 

Inclusion – An inclusion is a particle of foreign matter contained within a stone. Inclusions can be solid, liquid, or gas. Some inclusions decrease the value of a stone, but some, like rutile forming asterisms in star sapphires and needles in rutilated quartz and tourmalated quartz, are prized.

Karat – Karat is not the same as “carat”. Karat is a measure of the purity of gold. 24 karat gold is pure gold. 14 Karat gold is 14 parts gold and 10 parts other metals.

Opaque – Opaque stones do not allow light to pass through them. Jasper, Seraphinite, Charoite and are examples of opaque stones. 

Translucent – Translucent stones allow light to pass through them, but the light is scattered (diffused). Some translucent stones include moonstones, opals, and carnelian. Lucite and other plastics can also be translucent. The light is passing through the stone tending to make a glow.

 Transparent – Transparent stones allow light to pass through them without scattering (diffusing) the light. Some translucent stones include diamond, zircon, emerald, quartz crystal, and ruby. Plastics like lucite can also be transparent. 

Also see my information on the jewelry materials I use.