| Most of diamonds produced in the world are used in jewelry. Jewelry, i.e. those made from precious metals, may contain precious or semiprecious stones or may have no stones. The following are the kinds of works for which appraisal is not conducted:
Large diamonds with a high color and cut quality should be unmounted before grading. A jewelry work should be carefully washed before grading.
The succession of quality evaluation of jewelry works:
Jewelry works differ in complexity, type of mounting, purity of precious metal used, etc. When grading of a mounted diamond is performed, type of mounting and color of the metal are of primary importance. The commonly used mounting types include a jour (providing the best access to a stone), gypsy setting (most difficult for grading), corner, rail.
Mounting is usually made from gold of various colors, platinum, silver, and palladium of various purity. The mounting type and the color of the metal used significantly affect the visual perception of a stone and thus complicate grading.