摘要
大庙矿产在石榴石角闪石辉石岩中的含钴、铜的铂矿脉中。它常呈直径为1.0—2.0mm的小圆球与伊逊矿紧密共生;不透明,金属光泽;颜色为钢灰色,条痕黑色;莫氏硬度H_M 5.3,显微硬度VHN_(50) 485 kg/mm^2(范围434—529 kg/mm^2);无解理;计算密度D_(calc.) =10.95 g/cm^3。9个电子探针分析的平均化学成分为(％):Pt 45.6,In 53.5。化学式为:PtIn_2。6条最强X射线衍射线(hkl,d,I)为:220,2.25(100);311,1.92(60);400,1.59(60);422,1.299(80);440,1.125(60);620,1.006(70)。X射线粉晶衍射线图谱指标化后求得该矿物为等轴晶系,空间群:Fm3m。α=0.6364(3)nm。V=0.25775nm^3。Z=4。
Damiaoite was found in a cobalt-. copper-bearing platinum vein in garnet-amphibole pyrox-enite(a contant zone of pyroxenite with granite) which is situated near the Yixun River. The chief ore minerals are bornite, chalcopyrite, magnetite and carrolite. Damiaoite occurs as immiscible gloubles 1. 0-2. 0 mm in diameter (product of complexing in hydrothermal solution). It is associated with moncheite, sperrylite and cooperite in chalcopyrite. Damiaoite was also obtained from heavy concentrates of crushed ores. It occurs as single gloubles or as exsolution from yixu-nite. Opaque with metallic luster; colour bright white with a black streak; HM = 5. 3; VHN50 = 485 kg/mm2 (range 434-529 kg/mm2); insoluble in HC1, HNO3, HF and H3PO,; cleavage none; magnetic none. Density could not be measured because of the small grain size. Density (calc. ) = 10. 95 g/m3. Relfective colour is bright white with a yellowish tint. Isotropic. The bireflectance and pleochroism in air not observed. Reflectance values were measured in air by using WTiC as standard. Nine chemical analyses were carried out by means of an electron micro-probe using following standards: pure metals PtLa and InLa. The mean analytical results (and ranges) (%) are: Pt 45.6 (45.4-46. 0), In 53. 5 (52. 4-53. 9), and total 99. 1. The empirical formula (based on 3 atoms) is: Pt(1.002)In<(1.998) The X-ray powder diffraction was studied with Mn-filtered Fe radiation by a 57. 3 mm diameter Debye camera. Damiaoite powder patterns are similar to those of artifical PtIn2. It could be indexed on a cubic unit cell with a space group Fm3m. After refinement from the powder data we obtain: a = 0. 6364 (3) nm, Z=4.It is named after its locality which is situated near the village of Damiao, about 270 km N of Beijing.
出处
《地质学报》
EI
CAS
CSCD
北大核心
1997年第4期328-331,共4页
Acta Geologica Sinica
基金
国家自然科学基金(编号49172082)
关键词
新矿物
大庙矿
铟
铂
天然合金
new mineral, damiaoite,cobalt-, copper-bearing platinum vein,garnet-amphi- bole pyroxenite
