Diamond Glossary

The knowledge and more information you have the better diamond purchase you will make. Here are a number of diamond terms that are used by jewelers to describe diamonds and which appear on diamond grading reports.

B:

Blemish:
A clarity characteristic that occurs on the surface of a diamond. Though some blemishes are inherent to the original rough diamond, most are the result of the environment the diamond has encountered since it was unearthed.

Brilliance:
The brightness that seems to come from the very heart of a diamond. It is the effect that makes diamonds unique among all other gemstones. While other gemstones also display brilliance, none have the power to equal the extent of diamond's light-reflecting power. Brilliance is created primarily when light enters through the table, reaches the pavilion facets, and is then reflected back out through the table, where the light is most visible to your eye.

Brilliant Cut:
One of three styles of faceting arrangements. In this type of arrangement, all facets appear to radiate out from the center of the diamond toward its outer edges. It is called a brilliant cut because it is designed to maximize brilliance. Round diamonds, ovals, radiants, princesses, hearts, marquises, and pears all fall within this category of cut.

Brilliant:
Symmetrical cut with a round girdle outline, featuring 56 facets.

Bezel:
A facet on the Crown, or upper part of the Diamond above the Girdle.

Bezel Facets:
The eight large, four-sided facets on the crown of a round, brilliant-cut gem, the upper points of which join the table and the lower points, the girdle. Some diamond cutters further distinguish four of these as quoin or top-corner facets.

Bow Tie Effect:
An effect caused by a shadowy area visible in some fancy shapes, caused by light leaking out the bottom of the Diamond.

Bruise:
An inclusion consisting of surface crumbling, often accompanied by tiny, root like feathers.

Baguette:
A step cut in the shape of a small rectangular stone. May be tapered at one end.

Bearded girdle, or Bearding:
Tiny, numerous, hairlike fractures extending into the stone. If a diamond is rounded up too quickly in the fashioning process, the surface of the girdle will lack the smoothness and waxy luster of a finely turned girdle. Consequently, numerous minute, hairline fractures extend a short distance into the stone. A girdle with this appearance is referred to as being bearded or fuzzy.

Bort:
Industrial grade diamonds

Burned Facet:
This facet may appear whitish, or burnt, as a result of the cutter polishing the facet "against the grain".

Bruting:
Cutting step involving rough diamonds which produces the basic shape outline.

Butterfly:
Term used to describe the dark area located across a table, sometimes found in fancy shapes

Beard:
Feather-like inclusions located on the girdle resulting from poor bruting.

Black Diamond:
When a diamond is dark gray, a very dark green or truly black, it is referred to in the trade as a “black diamond.” Such a stone may be opaque to nearly semitransparent.

Blue Diamond:
A diamond with a distinctly blue body color, even thought very light in tone, is a fancy diamond. Diamond that are blue in both daylight and incandescent light are rare, although fluorescence stones that show a blue color in daylight are comparatively common. A blue color may also be induced artificially.

Blueground:
A miner’s nickname for kimberlite, the rock that contains diamonds in the South African pipe mines.

Blue White:
A term that has been used for many years to refer to a diamond without body color. However, it is applied frequently, but incorrectly, to stones that have a distinct yellow tint. Federal Trade Commission rulings state that is it an unfair trade practice to apply the term to any stone having a body color other than blue or bluish. An American Gem Society ruling prohibits the use of the term by its members. Flagrant misuse has made the term meaningless.

Body Color:
The color of a diamond as observed when examined under a diffused light against a hueless background free from surrounding reflections. The diffused light eliminates glaring reflections and dispersion, which would otherwise confuse the color determination.

Bombarded Diamond:
A diamond that has been subjected to bombardment by fast electrons, neutrons, deuterons, etc. The purpose of bombardment is to make the color of the stone more attractive and desirable.

Brillianteering:
The placing and polishing of the 40 remaining facets on a brilliant-cut diamond after the main bezel and pavilion facets have been placed and polished.

Brown Diamond:
Although not as frequently encountered as a yellow body color, brown tints in diamonds are next to yellow in occurrence.

Bubble:
Any transparent inclusion in a diamond; e.g., a tiny diamond crystal or a grain of a different mineral.

Break Facets or Girdle Facets:
The 32 triangular facets that adjoin the girdle of a round brilliant-cut stone, 16 above and 16 below. Also called upper- and lower-girdle facets, upper- and lower-break facets, top- and bottom-half facets, skew facets or cross facets. Facets are sometimes placed directly on the girdle, in which case the stone is usually said to have a faceted girdle, to have a polished girdle or to be girdle faceted.

Bar setting:
Similar to the channel setting, it is a circular band of diamonds that holds each stone in by a long thin bar, shared between two stones. Click here to learn more about ring settings.

Barion cut:
This has a traditional step-cut crown and a modified brilliant-cut pavilion. A square barion cut diamond has 61 facets, excluding the culet. Click here to learn about cutting styles.

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