Term
|
Definition
| a small, four-sided step cut that's rectangular, square or tapered |
|
|
Term
|
Definition
| clarity characteristic that's confined to the surface of a polished gemstone |
|
|
Term
|
Definition
| cutting style that's developed, named, and promoted by a specific manufacturer |
|
|
Term
|
Definition
| the brightness created by the combination of all the white light reflections from the surface and inside of a polished diamond |
|
|
Term
|
Definition
| cutting style with triangular or kite-shaped facets that radiate from the center toward the girdle |
|
|
Term
|
Definition
| the collective term for inclusions and blemishes |
|
|
Term
|
Definition
| top part of the gem above the girdle |
|
|
Term
|
Definition
| small facet at the bottom of a finished gem |
|
|
Term
|
Definition
| a gemstone's ability to withstand wear, heat, and chemicals |
|
|
Term
|
Definition
| a flat, polished surface on a finished gem |
|
|
Term
|
Definition
| any gemstone shape other than round |
|
|
Term
|
Definition
| the flashes of color you see in a polished diamond |
|
|
Term
|
Definition
| four value factors (clarity, color, cut, and carat weight) that describe the quality of a finished diamond |
|
|
Term
|
Definition
| rough gem material that requires normal processing to produce a polished gem suitable for use in jewelry |
|
|
Term
|
Definition
| the narrow section of a finished gem that forms the boundary between the crown and the pavilion and functions as the gem's setting edge |
|
|
Term
|
Definition
| how well a gemstone resists scratches and abrasion |
|
|
Term
|
Definition
| clarity characteristic totally enclosed in a polished gemstone or extending into it from the surface |
|
|
Term
|
Definition
| rough gem material suitable for use in tools, drills, abrasives, and other industrial applications |
|
|
Term
|
Definition
| a unit of measure for the fineness of gold, abbreviated "K" or "Kt" |
|
|
Term
|
Definition
the international unit of measurement for gem weight
one carat=1/5 of a gram (0.200 g) |
|
|
Term
|
Definition
| cut that combines brilliant-cut and step-cut styles |
|
|
Term
|
Definition
ranking of the relative hardness of 10 minerals
1-talc, 2-gypsum, 3-calcite, 4-fluorite, 5-apatite, 6-orthoclase feldspar, 7-quartz, 8-topaz, 9-corundum, 10-diamond |
|
|
Term
|
Definition
| rough gem material that requires substantially more processing than gem-quality rough to produce a polished gem suitable for use in jewelry |
|
|
Term
|
Definition
| lower part of a faceted gem below the girdle |
|
|
Term
|
Definition
| one hundredth of a carat (0.01 ct) |
|
|
Term
|
Definition
| the flashes of light you see when the diamond, the light, or the observer moves |
|
|
Term
|
Definition
| a natural or man-made material that resembles a gem (also called imitation) |
|
|
Term
|
Definition
| a round stone with 17 or 18 facets |
|
|
Term
|
Definition
| how well a diamond resists chemicals and temperature changes |
|
|
Term
|
Definition
| a round brilliant-cut stone with 57 or 58 facets; often called a full cut |
|
|
Term
|
Definition
| a cutting style that features long, narrow facets in rows (usually three) parallel to the girdle on both the crown and the pavilion |
|
|
Term
|
Definition
| a man-made gem with essentially the same chemical composition, crystal structure, and properties as a natural gem |
|
|
Term
|
Definition
| damage caused by sudden, extreme temperature changes |
|
|
Term
|
Definition
| how well a gemstone resists breaking and chipping |
|
|
Term
|
Definition
| features used to judge the quality and value of all gemstones |
|
|
