宝石的致色与改色

颜色是评价宝石的重要参数．使宝石致色的机理有多种．一部分宝石由于天然生成的颜色不理想，不能成为优质宝石，须人工改色才能成为人们喜爱的饰品．宝石致色的本质，实际上是过渡金属元素的内部电子跃迁，元素离子间的电子转移或电荷转移，晶体结构缺陷造成的电子转移等．宝石的改色研究目前已引起了国际性的关注，并成为宝石学的重要内容之一．

Colourating Mechanism and Colour-Changing of Gems

Colour is an important parameter for gem evaluation. There are different kinds of gem colourat ing mechanisms. Some stones may not be high quality gems bucause of their unsatisfactory natural colours.They can not become the jewelery loved by consumers unless their colours are changed artificially. The essen tial of colourating is the transition of the internal electrons of transition-metals, the electron or charge trans fer between ions, and the electron transfer caused by the faults in crystal structure. Close attention has been paid to the research of colour changing of gerns in the world, which becomes the important content of gemology.