萤石染色机理初析——以武义萤石为例

萤石的颜色主要是其中混入杂质元素造成。碱土金属矿物因类质同像而易被过渡元素和稀土元素所取代.外来元素的加入造成了晶格常数的变化产生各种色心.过渡金属元素存在不同价态的离子有利于电荷的转换或转移.稀土元素在辐射和热力作用下电价亦可起变化.使不同波长光波选择吸收及透射,在表生作用下,浅表性质子交换.易被氧化和羟基化.F~-晶位被OH~-和(D~-).2F~-被O~(2-)取代而成色核.

ON FLOURITE COLOR-CAUSING MECHA NISM-AN EXAMPLE FLOURITE FROM WUYI

Impurities mixed in flourite give rise to its coloration. The alkaline earth metals being easily replaced by transitional elements or rare earth in isomorphie replacement, color centrs form due to changes of cell parameters be caused by the exotic. These ions with different valences in transitional metal elements or valence changes of rare earth elements under radiation or thermodynamical effect can cause selective absorption or penetration to light with different wavelengths at lead to flourite coloration, flourite is oxidated or hydroxylateddurningthe surface ion exchanges; crystallographic sites of F- is occupied by OH- (D-) and the sites of 2F- by O2- , giving birth to cell centres.