At last, the appraising standards of the cut quality of gem corundum are probed from the aspects of orientation, shape of cut, proportion, symmetry and polish.

 
  • 从定向、琢型、比例、对称程度和抛光修饰度等方面探讨了刚玉宝石的切工质量评价标准。
今日热词
目录 附录 查词历史