Glossary of Common Jewelry Terms

4 C's

A universal grading system developed by GIA (Gemological Institute of America) to evaluate the quality of a diamond. The 4 C's are Carat, Color, Clarity, and Cut.

Alloy

A mixture of two or more metals to create more desirable characteristics and/or added strength

Baroque

An irregular-shaped stone or pearl. Also an art style characterized by ornate detail.

Base Metal

A term informally referring to non-precious metals (such as copper, zinc, tin, nickel, lead or iron), which are commonly used in costume jewelry.

Brilliance

Pertaining to diamonds, this term has two components: brightness and contrast. Brightness refers to the amount of light returned from the diamond's surroundings and back to the observer. To be brilliant, a diamond also needs contrast, intensity of the white light from the crown of a polished diamond or other gemstone.

Cabochon

A polished, convex-cut, unfaceted gemstone. Typically has a flat back.

CAD/CAM

Computer-aided design and manufacturing.

Cameo

A design cut in relief, usually into a hard gemstone or shell.

Carat

A unit of weight for precious and semi-precious gemstones, equal to 200 milligrams.

Comfort-Fit

Describes the convex interior of a ring.

Contemporary

Designs that are up-to-date with current trends in the industry with a modern flair.

CZ

Short for Cubic Zirconia, a man-made gemstone created to simulate a diamond. Approximately 64% heavier than a diamond.

Dispersion

The power of a diamond when breaking up its light into its constituent colors.

DWT

Abbreviation for pennyweight. There are 20 pennyweights in an ounce (Troy).

Enamel

An opaque or semi-transparent glass or substance applied to a metal surface for protection or ornamental purposes.

Facet

The flat, polished surface of a gemstone that affects a gemstone's brilliance and sparkle.

Filigree

Lace-like ornamental work formed from thin wires of intricately-arranged intertwined precious metal. May be plain, twisted, or plaited.

Finding

A component or part used in the making of a piece of jewelry.

Finish

A decorative texture applied to the surface to enhance it's appearance.

Fire

Dispersed light that appears as flashes of spectral colors (rainbow) on a diamond.

Gemstone

A mineral or organic material with sufficient beauty, rarity, and durability to be set into jewelry.

Genuine Stone

A gemstone that is produced by nature without interference from man, other than cutting or fashioning. Do not confuse "natural" with untreated gemstones.

Hallmark

A quality mark indicating precious metal content (10kt, 14kt, 18kt, platinum, etc.). Typically stamped on a jewelry item in an inconspicuous location (back, inside ring shank, etc.). FTC requires the manufacturer or distributor of said product to disclose their identity by accompanying the quality mark with a trademark or company name.

Hypo-Allergenic

A term used to describe items (in this case jewelry) that cause or are claimed to cause fever allergic reactions. Depending on the allergen of the subject, these may include metals such as stainless steel, titanium, gold, etc.

Inlay

The insertion of pieces of gemstones, wood, ivory, etc. into slots created on the surface for embellishment.

Karat

A unit of measure of the purity of gold. Pure gold equals 24 karats.

Melee

Classification used in the sorting of diamonds weighing less than .17 carats or 17 points each.

Milgrain

Having the edge shaped into fine beading.

Moissanite

A rare mineral discovered by Henri Moissan, later synthesized in the laboratory and used as a high-quality diamond substitute.

Mounting

A jewelry item that has stone settings, but in which no stones have been set.. It requires no further assembly work; the exception being an unset semi-mount mounting which requires a head to be attached.

Patina

Discoloration that forms naturally over time on metals such as silver and bronze. Patinas may also be introduced artificially through certain chemicals for aesthetic value.

Pennyweight

Pennyweight is a common weight unit of measure used in the valuation and measurement of precious metals. One pennyweight equals 1/20 of an ounce (Troy).

Precious Metals

Metals that are rare and have high economic value. Gold, silver, platinum, and palladium.

Precious Gemstone

The group of gemstones consisting of diamonds, rubies, sapphires and emeralds.

Primary Metal

The metal alloy that, when describing a two-tone item, makes up the majority of the weight of the jewelry item.

Prototype

An example of a piece of jewelry created from inexpensive, non-precious materials.

Scintillation

The intense sparkles and flashes of light visible when either the person viewing the diamond or the lighting moves.

Secondary Metal

When describing a two-tone item, the metal alloy that makes up the minority of the weight of the jewelry item.

Semi-Precious Gemstone

A gemstone that is not a diamond,n emerald, sapphire or ruby – historically thought to be less valuable than a precious gemstone, i.e., amethyst, peridot, aquamarine, etc.

Setting

The act of securing a gemstone. The term setting is sometimes used interchangeable with head and/or mounting.

Work-Hardened

The change in hardness of metal due to repeated cold flexing or stress. The annealing (heating) process can be used to relieve stress.

Source: Stuller