Colored Stones Key Terms PDF

Colored Stones 9 Key Terms Brilliance—Light that eventually returns to the eye after Grinding—Giving approximate shape to a gemstone, or entering a gem through the crown, reflecting off its producing flat planes for polishing facets. pavilion facets, and exiting back through the crown....

Colored Stones 9 Key Terms Brilliance—Light that eventually returns to the eye after Grinding—Giving approximate shape to a gemstone, or entering a gem through the crown, reflecting off its producing flat planes for polishing facets. pavilion facets, and exiting back through the crown. Intaglio—A design engraved into the surface of a Brilliant cut—Cutting style with triangular or kite-shaped gemstone. facets that radiate from the center toward the girdle. Lap—Horizontal spinning metal disk used to grind or Cabochon—A smoothly rounded polished gem with a polish a gem’s facets. domed top and a flat or curved base. Cameo—A gem carving style in which the design, often a Mixed cut—A cutting style that combines brilliant-cut and woman’s profile, projects slightly from a flat or curved step-cut facets. surface. Pavilion—Lower part of a faceted gem below the girdle. Cobbing—Removing heavily included sections from gemstone rough by carefully tapping it with a small hammer. Polishing—Final stage in gem cutting that produces the smoothest possible surface. Crown—Top part of the gem above the girdle. Preform—Rough ground to the approximate shape of the Crown-height to pavilion-depth ratio—The relationship of finished stone; also, the act of producing this shape. the height of a gem’s crown to the depth of its pavilion, judged by viewing its profile. Proportions—The angles and relative measurements of a Designer cuts—Artistic gem cuts that aren’t limited to polished gem, and the relationships between them. specific proportions or shapes. Sawing—Dividing gem rough into easily handled pieces Dopstick—Wooden or metal stick that holds the preform and removing waste areas. during faceting. Step cut—Cutting style with mainly square and Faceting head—Device that holds the dopstick at precise rectangular facets arranged in concentric rows. angles to allow correct orientation during faceting and polishing. Style—The arrangement of a stone’s facets. Fantasy cut—A free-form cut that can feature alternating curved and flat surfaces. Symmetry—The precision and balance of the corresponding parts of a finished gem. Girdle—Narrow section that forms the boundary between the crown and the pavilion, and functions as the gem’s Table facet—Facet at the top of the crown, usually the setting edge. largest facet on the stone. 148