山东省白彦地区绿色金刚石特征及宝石学意义

Features and gemological significance of green diamond from Baiyan,Shandong Province

山东省沂蒙山的白彦地区,以往地质工作中已发现数干颗金刚石,其中有多量的绿色和带绿色斑点的晶体。金刚石晶体颗粒细小,表层具有深绿斑、褐色斑点,绿色不均匀,颜色有绿、蓝绿、褐绿、黄绿、灰绿、黑绿等色,晶体多不完整,磨损轻、微。枣庄市上泥河村底砾岩、花果泉第四系砂砾层中产出的绿金刚石具有绿色向褐色转变的特点。切磨过程中,绿色钻石具热作用下的绿色不会消失,但会出现绿色纯度或明暗度、鲜艳度存在不确定的游移性变化特征,甚至出现新的附加色,或者消失原来的附加色。这种变化现象具宝石学意义。

Previous geological work has found thousands of diamonds from Baiyan of Yimeng Mountain area,Shandong Province.These diamonds have plenty of green and green spots in crystals.The particles are fine,the surface has dark green or brown spots,and the color is uneven,exhibiting green,green,blue green,brown green,yellow green,gray green,or black green colors;the crystal is not complete,with light or micro wear.The green diamonds from the Shangnihecun conglomerate and the Quaternary fluvial sandstone and conglomerate of Zaozhuang City show a color pattern changing from green to brown.During the cutting and grinding process and the processing of green diamond with heating,the green color does not disappear,but the diamond changes in purity and brightness,or even shows new additional color or the disappearance of additional color.These changes are of gemological significance.