A Blog about the Fascinating World of Jewelry » jewelry glossary

Diamond Grading. A cavity is an equidimensional opening in the surface of a polished diamond, sometimes caused by a blow or the pulling out of a knot in polishing.

Cabochon is an unfceted form of gemstone cutting, used for opaque and translucent stones; the stone is given a rounded, convex shape.

Cat's Eye is the name given to a gem which, when cut cabochon, shows a single light streak across its face. It is caused by innumerable parallel inclusions, of minute needle-like crystals or tubular cavities, the sides of which reflect light.