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The Diamond Glossary

( Originally Published 1911 )

BAHIAS.— Brazil diamonds from the Bahia district.

BIZEL.—The upper portion, above the girdle, of a brilliant-cut diamond.

BLUE GROUND.— Unoxidized rock of the diamond chimneys. Boar.—Diamonds fit for mechanical purposes only.

BRUTING.— Polishing diamonds by rubbing them together. BUBBLES.— Small, hollow-appearing specks in the body of the stone. BYWATERS.--Decidedly yellowish diamonds.

CAPES.— Yellowish white diamonds.

CARAT.—An unofficial weight used for weighing precious stones. CARBON SPOTS.— Opaque black spots in diamonds.

CASCALHO.— Diamondiferous gravels, Brazil.

CHIPS.— Cleavage under three-fourths of a carat.

CLATERSAL.— Small diamond splints from which diamond powder is produced by crushing.

CLEAN.— Free from noticeable flaws.

CLEAVAGE.— Diamond crystals which require cleaving, also pieces cleaved, and large fragments.

CLOUDS.— Flat, subtransparent blotches along the grain of the stone. CLOSE-Goods.— Diamond crystals requiring no preparation for cutting.

COLOR-PLAY.— Prismatic colors produced by dispersion.

COMPOUND.— An enclosure at Kimberley in which the natives are held while they work in the De Beers Consolidated Mines. CRYSTALS.— White diamonds.

CULET.— Small flat facet at the bottom of a brilliant-cut diamond.

DIAMOND DRILLS: Cylindrical iron pipes having carbon or bort set in the edge as teeth, for drilling.

Du.— Device for holding diamond during the process of cutting and polishing.

ESTRELLADA.— Decomposed stratified rock showing starry white points. A diamondiferous deposit of Brazil.

EXOTIC-FRAGMENTS: Inclusions of foreign rock unlike surrounding reef, found in diamond chimneys.

FALSE COLOR.— Diamonds showing different tints of color in different lights.

FANCIES.— Diamonds of fine and decided colors.

FEATHERS.— White, subtransparent lines in the body of the stone. FISH-EYE.—Diamond cut too thin to secure the angle of total reflection from the interior facets.

FLATS.- Thin diamond crystals or parts of crystal used for draw-plates.

FLOATING-REEF.— Inclusions of surrounding reef in the rock of the diamond chimneys.

FLOORS.— Level stretches of ground on which the diamondiferous rock of the African Mines is weathered.

GIRDLE.— Edge of brilliant-cut diamond at junction of pavilion and bizel: greatest circumference edge.

GLASSIES.— Transparent diamond crystals.

GLASSY.— Diamonds lacking sharpness of brilliancy.

GLAZIERS' DIAMONDS.— Small diamonds or corners of diamond crystals, used for glass cutting.

GLESSEN.— Semi-transparent fissures in diamonds. Feathers. GOLCONDAS: Indian diamonds, as generally applied.

GORGULHO.— Diamondiferous quartz and clay gravel of Brazil. GRAIN MARKS.— Lines on the facet surfaces due to imperfect polishing.

GRUPIARAS.— Shallow deposits of diamondiferous gravel on the river hills of Brazil.

I. D. B. ACT.— A law passed in Cape Colony, South Africa, making illicit diamond buying a criminal offense.

JAGERS.— Fine white diamonds, tending to a blue tint.

KIMBERLITE.— A serpentive breccia named after Kimberley, where it was discovered as a diamond-bearing rock.

KNIFE-EDGE.— The girdle of a diamond cut to a sharp edge. KOPJE.—A small hill in the Boer country of Africa.

LUMPY,— Said of stones cut too thick

MACLES — Twinned crystals in which the junction is not distinct. MAHABHARATA.- Hindu epic.

MANGELIN.- Hindu weight equal to 13g carat.

MELANGE.- Mixed sizes.

MELEE.— Small diamonds.

MUDDY.- Lacking internal brilliancy.

NAATS.— Thin flat crystals.

NAIFES.— Hindu name for shapely uncut diamonds. NIT.— Outer part or skin of the diamond crystal.

OFF-COLOR.-Having a tint of undesirable color. OLD-MINE.- Old-cut diamonds of good color.

PAGODA.- Hindu money worth eight shillings British.

PAVILION.- Under part of brilliant-cut diamond.

PREMIERS.— Diamonds from the Premier Mine ; as commonly used, diamonds having an oily luster or false color.

RATI—Hindu weight, variable in quantity of mass according to use, time and place.

REEF.— Strata of earth surrounding diamond chimneys. REJECTIONS.- Diamonds thrown out of the mixed lots as undesirable.

RIVERs.—Diamonds from the rivers or wet diggings of Africa. ROUGH.- Uncut crystals.

ROUND-STONES.- Diamond crystals with curved facets, and roundish or water-worn crystals.

SECUNDINA.- A clay schist which usually overlays the diamondiferous deposits of western Minas Geraes, Brazil.

SHARPS.- Thin, knife-edge pieces of diamond crystal.

SIGHT.- Opportunity afforded buyers by the Diamond Syndicate to view the original parcels of rough.

SILVER-CAPES.- White diamonds with a slight tint of yellow. SPECIFIC GRAVITY.- Relative weight of bulk as compared with distilled water at 6o° F.

SPLINTS.- Sharp-pointed diamond splinters, or cleavages less than one carat.

SPREAD.— Surface in proportion to the depth of a cut stone.

TABLE.— Large flat facet on top of brilliant-cut diamond. TAU—A breccia of the Agua Suja district, Brazil, particularly rich in diamonds.

TORN-END.— Three-cornered pyramid from the point of a wassie; a corner.

TWINNED.—Crystals formed conjunctively.

Twins.—Crystals which show the junction of the crystals distinctly.

WASSIE.— A large cleavage split for cutting.

WELL.—Dark center of a diamond cut too thick. Wesseltons.—Fine white diamonds supposed to come from the Wesselton Mine.

YELLOW-GROUND.— Upper part of the diamondiferous rock in the African chimneys; oxidized blue-ground.

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