Abstract:
Turquoise is a sky-blue mineral aggregate of hydro-phosphate with copper and aluminum, and with particular fashion properties such as lower hardness, lower toughness, porous structure, sensitivity to acid, alkali and high temperature, etc. On the basis of systematical fashion properties and variety classification of turquoise, the cut designs are discussed and the skills in fashion are studied emphatically. The results indicate that the process of fashion as dividing(sawing), performing(shaping), cutting and polishing must be in the cold-finished condition and raw turquoise must be kept clean avoiding acid and alkali. The turquoise is polished by felt buff, bristle wheel or felt cone, and finally treated by wax. The appraising standards of the fashion quality of turquoise are briefly probed from the aspects of shape of cut, symmetry, proportion and polishing.