Diamond Glossary - Black Diamond, Blue Diamond, Bow Tie Effect

This is our diamond glossary of terms used in the diamond jewelry business....
facts about diamonds-

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Diamond Glossary - B

Baguette: A French word meaning rod or stick. A style of step cutting for small, rectangular or trapeze-shaped gemstones, principally diamonds used as accent or side stones.

Bar Setting: A diamond setting style that holds each diamond in by a thin bar, shared between the two diamonds.

Barion Cut Diamond: This has a traditional step-cut crown and a modified brilliant-cut pavilion. This is referred to as a mixed cutting style. A square Barion Cut diamond has 61 facets, excluding the culet.

Baroque: Irregular in shape, such as baroque pearls, tumble-polished stones, or freeform shaped gem materials.

Bearded Girdle: Tiny, numerous, hairlike fractures extending into the diamond. The outermost portion of the diamond, called the girdle, can develop small cracks that resemble whiskers during the shaping process. If a diamond is rounded up too quickly in the shaping process, the surface of the girdle will lack the smoothness and waxy luster of a finely turned girdle. The bearding can sometimes be removed, if not too dramatic, with slight re-polishing, and if the finished weight allows it.

Bezel Facet: On a Round Brilliant Cut diamond, these are eight large kite-shaped facets on the crown, the upper points of which touch the table and the lower points, touch the girdle. Also called top main facet. Some diamond cutters further distinguish four of these as "quoin" or "top-corner" facets. bezelsetting

Bezel Setting: A rim that holds the diamond and completely surrounds the diamond along the area just above the girdle. Bezels can have straight edges, scalloped edges, or can be molded into any shape to accommodate the diamond.

Birthstones: Birthstones have their roots in ancient astrology, and there have been many birthstone lists used over the years. The most common one today is based on a list first publicized by the U.S. jewelry industry in the 1950s. This list assign birthstones as follows-

January	Garnet
February	Amethyst
March	Aquamarine
April	Diamond, Yeah!!!
May	Emerald
June	Pearl, Alexandrite
July	Ruby
August	Peridot
September	Sapphire
October	Opal, Pink Tourmaline
November	Yellow Topaz, Citrine
December	Blue Topaz, Turquoise, Zircon

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 semi-transparent.

Blemish: Any surface imperfection on the surface of a diamond, such as a nick, knot, scratch, abrasion, minor crack or fissure (cavity), or a poor polish. Also, a natural or an extra facet, visible on or through the crown, usually is considered a blemish.

Blue Diamond: A diamond with a distinctly blue body color, even if it is very light in tone, is a fancy blue diamond. Boron that is present in the crystal structure is responsible for this color. A blue color may also be induced artificially and is referred to as a color enhanced diamond.

Blue White: This is a term that I haven't heard in many years... actually it was probably last century! It was still commonly used up till the mid 60's. Federal Trade Commission rulings state that is it an unfair trade practice to apply the term to any diamond 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 of this term has made it meaningless and it is no longer used.

Blueground: A miner's name for "kimberlite", the rock that contains diamonds in the South African pipe mines.

Body Color: The color of an unmounted diamond as observed when examined under a diffused light against a hueless (colorless) 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 a stream of fast electrons, neutrons, deuterons, etc. The purpose of bombardment is to alter the color of a diamond.

Bort: Industrial grade diamonds.

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. A large bow-tie in the center of a fancy shaped diamond detracts from beauty and lowers the value. (also 'Butterfly')

Brilliance: The total amount of white light returned to the eye from a diamond or colored stone as the result of internal and external reflections. The major factors that affect the amount of brilliancy in a gem are refractive index, proportions, polish and transparency.

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, oval, radiant, princess, heart, marquise, and pear shape diamonds all fall within this category of faceting style.

Brillianteering: The placing and polishing of the 40 remaining facets on a single cut diamond after the 8 main bezel, 8 pavilion main, and the table have been placed and polished. By adding the additional it is now called a "full cut" diamond.

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

Bruise: Inclusions consisting of surface crumbling, often accompanied by tiny, root-like feathers .

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

Burned Facet: This facet may appear whitish, or burnt, as a result of the cutter polishing the facet "against the grain". The excessive heat of polishing will make the diamond red hot and the surface will actually start to burn. This can also happened if the diamond is not properly protected from exposure to the atmosphere while being heating during repair work. A burnt facet can be re-polished.

Butterfly: Term used to describe the dark area located across a table, sometimes found in fancy shapes (see 'Bow Tie').

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