安徽马鞍山假象绿松石、磷铝石成因探讨

摘要

利用偏反光显微镜鉴定、稀土元素化学分析等方法对马鞍山相关矿物岩石进行岩相学、矿物学、化学成分研究及对比，发现假象绿松石镜下结构具球粒状变胶结构，其稀土元素大幅流失，与风化围岩及其他产状绿松石相当；假象磷铝石具有磷灰石双锥柱状，磁铁矿包体特征与原磷灰石具有一致性，其稀土成分、含量与原磷灰石具有高度继承性。据此对假象绿松石、磷铝石的成因进行分析探讨。%Petrographic, mineralogical study, chemical composition study and comparison using polarizing, reflective microscope, REE chemical analysis of relevant mineral and rock in Maanshan indicated that pseudomorphic turquoise takes the pelletoid metacolloidal form, and its REEs have been largely depleted, like the weathered wall rock and turquoise of other occurrences; pseudomorphic variscite has double cone-cylinders of apatite, magnetite inclusion has the feature consistent with that of original apatite, and its REE composition and content are highly inherited from the latter. On the above basis, a discussion was made on the origin of pseudomorphic turquoise and variscite.