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antwerp diamond house, diamonds and jewelry

So... you may want to get to know it all.
I have listed here most of the terms used in our diamond industry.
I welcome all inquiries, so feel free to contact me with any question you may have or quotation you may require for diamonds or jewelry.
For exclusive chronometers and other high-class watches I do recommend my other site at: Watches at Diamond House.

ion tte ed Diamond Center Drill Hole etc.
Term Glossary of diamonds by Antwerp Diamond House
Tiny nicks along facet junctions, producing white fuzzy lines instead of sharp crisp facet edges.
Antwerp Also called Antwerpen in Flemish, Anvers in French. Diamond center of the world, 2nd largest port of Europe on the river Scheldt, Belgium. Home town of Antwerp Diamond House.
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.
Bezel A facet on the Crown, or upper part of the Diamond above the Girdle.
Blemish Surface imperfection external to the 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.
Bruise An inclusion consisting of surface crumbling, often accompanied by tiny, root like feathers .
Burned Facet This facet may appear whitish, or burnt, as a result of the cutter polishing the facet "against the grain".
Carat Weight The metric carat, which equals 0.200 gram, is the standard unit of weight for diamonds and most other gems. If other factors are equal, the more a stone weighs, the more valuable it will be.
Cavity An inclusion consisting of a large or deep opening in the stone.
Certificate Laminated document by a gemological institute to describe a Diamond's characteristics.
Chip A tiny piece missing, caused by normal wear and tear, or by cutting.
Clarity A stone's relative position on a flawless to imperfect scale. Clarity characteristics are classified as inclusions (internal) or blemishes (external). The size, number, position, nature, and color or relief of characteristics determine the clarity grade. Very few diamonds are flawless, that means, show no inclusions or blemishes when examined by a skilled grader under 10X magnification. If other factors are equal, flawless stones are most valuable.
Cloud A group of tiny white inclusions which result in a milky or cloudy appearance.
A diamond colored by a surface coating which masks the true body color; the coating may be extensive (entire pavilion, for example), but is more often limited to one or two pavilion facets or a spot on the girdle.
Color Grading color in the normal range involves deciding how closely a stone's body color approaches colorlessness. Most diamonds have at least a trace of yellow or brown body color. With the exception of some natural fancy colors, such as blue, pink, purple, or red, the colorless grade is the most valuable.
Crown The upper part of the diamond above the girdle. Consists of a large flat area on top called a table, and several facets below it.
Culet The smallest facet at the bottom of the diamond.
Cut The proportions and finish of a polished diamond (also called make). Cut can also mean shape, as in emerald cut or marquise cut. Proportions are the size and angle relationships between the facets and different parts of the stone. Finish includes polish and details of facet shape and placement. Cut affects both the weight yield from rough and the optical efficiency of the polished stone; the more successful the cutter is in balancing these considerations, the more valuable the stone will be.
CZ Cubic zirconium. A widely used simulant, an imitation for a natural diamond. CZ, although easy detectable by its 80% higher weight than a diamond of the same prortions or by thermal conductivity testing, does often fool lay persons.
Emerald cut A step cut, usually rectangular.
Extra Facet A facet placed without regard for symmetry and not required by the cutting style.
Facet Plane, polished surface of a diamond.
Faceted Girdle Sometimes cutters polish the girdle into 32 facets.
Fancy Diamond A diamond with an attractive natural body color other than light yellow or light brown.
FAQ Frequently Asked Question. For FAQ's on diamonds for private buying see: Antwerp Diamond House FAQ's
Feather A separation or break due to either cleavage or fracture, often white and feathery in appearance.
Flaw An imperfection of a stone.
Fluorescence Mostly blueish glow of a Diamond in high ultraviolet lighting conditions. Ratings: none, faint, slight, medium, strong blue. Strong blue fluorescence may cause the Diamond to appear oily in daylight.
Fracture A crack on the Diamond's surface.
GGG Gadolinium Gallium Garnet, a modern imitation of a natural diamond; simulant.
GIA Gemological Institute of America. Reliable diamond certification. Diamond research.
Girdle The outer edge or the widest part of the diamond forming a band around the stone.
A small area of concentrated crystal structure distortion, usually associated with pinpoints.
Hardness Mineral's resistance to scratching on a smooth surface. Mohs scale of relative hardness consists of 10 minerals, each scratching all those below it in scale and being scratched by all those above it.
Hearts and Arrows A general term when referring to diamonds with a percise and complete pattern of hearts and arrows achieved by perfect cutting proportions. see FAQ
HRD Hoge Raad voor Diamant. An independent non profit institute in Antwerp for the Diamond industry. Reliable impartial Diamond certification controlled by Belgian state authorities.
Hue Pure, spectral (prismatic) color. Hues include gradations and mixtures of red, organdy, yellow, green, blue, violet and purple.
Imitation See simulants
Included Crystal A mineral crystal contained in a diamond.
Inclusion Imperfection internal to the Diamond.
Internal Graining Internal indications of irregular crystal growth. May appear milky, like faint lines or streaks, or may be colored or reflective.
Irradiated diamond A diamond which has been exposed to radiation.
Knot An included diamond crystal which reaches the surface of a polished diamond.
A tiny tube made by a laser. The surface opening may resemble a pit, while the tube usually looks needle like. May be noticeable on treated Diamonds.
Laser Indentification Microscopical small inscription by a laser on a diamond for indentification. Can be the diamond certificate number, a message, brandname and number or otherwise.
Loupe Magnifying glass usually of 10X.
Melee Small Diamonds under .20 carat. Usually .10ct diamonds.
Mohs scale The ten point scale of mineral hardness, keyed arbitrarily to the minerals talc, gypsum, calcite, fluorite, apatite, orthoclase, quartz, topaz, corundum, and diamond.
Moisannite A rare crystal in nature. Synthetically created moissanite produced by Charles & Colvard is a simulant ranking a high 9.25 on the Mohs hardness scale (Diamond = 10). Its double refraction is one of the few differences with a Diamond, thermal conductivity is almost equal.
Natural Part of the rough Diamond remaining on the Diamond, having survived the cutting process. This is usually the sign of a cutter attempting to maximize the weight retention of the rough Diamond. Frequently noticed on .00ct Diamonds in order to maintain a commercial interesting weight i.e. 2.00ct .
Needle A long, thin included crystal which looks like a tiny rod.
Nick A notch near the girdle or a facet edge.
Off Make A poorly proportioned Diamond.
Old European Cut Early round cut similar to the Round Brilliant Cut, but carrying a very small table and heavy crown. Not as popular today because it does not return the same brilliance as the modern brilliant.
Pavilion The bottom part of the Diamond, below the girdle.
Pinpoints Miniscule spots internal to a Diamond. A cluster of pinpoints can form a cloud.
Pit A tiny opening, often looking like a white dot.
Point 100th of a carat.
Polish Lines Tiny parallel lines left by polishing. Fine parallel ridges confined to a single facet, caused by crystal structure irregularities, or tiny parallel polished grooves produced by irregularities in the scape surface.
Polish Mark Surface clouding caused by excessive heat (also called burn mark, or burned facet), or uneven polished surface resulting from structural irregularities.
Rough Girdle A grainy or pitted girdle surface, often with nicks.
Round Brilliant cut The most common cut usually containing 58 facets. Also the most brilliant cut, in terms of most efficient use of light to increase brilliance and fire, hence the name.
Saturation A color's position on a neutral to vivid scale.
Scratch A linear indentation normally seen as a fine white line, curved or straight.
Spread stone A Diamond with a large table and a thin crown height.
Surface Graining Surface indication of structural irregularity. May resemble faint facet junction lines, or cause a grooved or wavy surface, often cross facet junctions.
Tone A color's position on a colorless-to-black scale.
Treated Diamond: Fancy color treatment: A diamond with a bodycolor induced by some form of artificial irradiation, often in conjunction with controlled heating (known as annealing). Other possible treatments of diamonds are: coating, fracture filling, spot bleaching by laser, electromagnetic conduction, whitening by extreme pressure and heat, ...
Twinning Wisp A cloudy area produced by crystal structure distortion, usually associated with twinning planes.
YAG Yttrium Aluminum Garnet, a modern simulant, so an imitation for a natural diamond
Zirconium, Zirconia Zr is a natural occurring metal. Synthesized in crystal form, cubic zirconia CZ, as simulant.

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