排序方式： 共有2条查询结果，搜索用时 53 毫秒
1
1.
新矿物二连石(Erlianite)产于海相火山沉积硅质建造,经变质的铁矿层中的破碎带。矿物呈黑色,条痕褐色。晶体成纤维状、鳞片状,集合体为规则的板柱状。不透明,丝绢光泽。H_v=3.7kg/mm~2,D=3.11g/cm~3。解理(001)和(100)完全。斜方晶系。晶胞参数:a=23.20,b=9.20,c=13.18,Z=1,可能的空间群为Pmmn或Pm2_1n。二轴晶负光性,N_(?)=1.667,N_(?)=1.674,N_(?)=1.679,2V=56—59°。化学式为:(Fe~(2+)_(19·96)Fe~(3+)_(2·19)Mg_(1·33)Mn_(0·42))_(23·90)(Fe~(3+)_(11·32)V_((?)·68))_(12)(Si_(34·73)Ti_(0·26)Al_(0·20)Fe~(3+)_(0·81))_(36)O_(90)(OH,O)_(48)(单位晶胞氧原子总数O=138)。 相似文献
2.
A Nb-, Ta-, rare metal deposit has been discovered in a albitization-, amazonitization-granite by using amazonite as an indicator. The ore-bearing dyke, early Yanshanian in age, occurs in a Late Jurassic metamorphic sandstone and breccia. Three stages of albite can be distinguished, showing regular variation in composition, optical property and structure with respective to different generations. Two generations of amazonite are noticed and studies are made on their composition and structure by using optical and X-ray diffraction methods. Amazonite is readily recognizable in the field by its colonr. Its occurrence with albitization can be used as a prospecting indicator for Nb, Ta and other rare metals. 相似文献
1