蔡承云石(Fe32+Al2(SO)6·30H2O) ———一种含水的硫酸盐矿物
来源期刊：中南大学学报(自然科学版)2002年第4期
论文作者：张如柏 张玉玉 洪洲 毛治华 刘发禄 习计
文章页码：331 - 334
关键词：蔡承云石;含水硫酸盐矿物; Pb-Zn矿床氧化带;四川会东
Key words：Caichengyunite; sulphate mineral; Pb-Zn deposite; Huidong, Sichuan
摘 要：蔡承云石产于四川省会东县的铅-锌矿床氧化带,与之共生的是铁的氢氧化物和水云母类的粘土矿物等,矿床的主要金属矿物是方铅矿、闪锌矿、黄铁矿和少量黄铜矿等.蔡承云石呈灰白色、纤维状、毛发状,具玻璃光泽,密度为2·20 g/cm3,硬度为1.5~2.0,易溶于水,在显微镜下为无色,无多色性,在温度为22℃时测得其3个光学主轴的参数为Ng=1.480 5,Nm=1.477 5,Np=1.475 6;用常规的化学方法分析蔡承云石的化学成分,其成分质量分数分别为:FeO,16.15%;Al2O3,7.90%;SO3,33.96%;H2O+,37.64%;H2O-,3.56%;不溶物,0.32%.以S的原子数为1时计算出蔡承云石的化学式为Fe32+Al2(SO4)6·30H2O;蔡承云石强X射线结果为:5.494(14,121),4.886(100,131),4.030(9,060),3.776(21,124),3.504(9,115),3.252(13,036),2.727(12,205),1.863(8,229),属单斜晶系,晶胞参数a=0.763 nm,b=2.413 nm,c=2.264 nm,β=111.06°,Z=4.
Abstract: The Caichengyunite occurs in the oxidized zone of the Pb-Zn ore-deposit atLongshuVillage, Huidong County,Sichuan Province. Associated minerals are pyrite, galena, sphalerite, limnite and clay minerals. The mineral is on the undergroundwall, which is filiform and fibrous, transparent and non-fluorescent, and displays greyish white colour,white streak and vitreous luster, its Mohs handness is 1.5~2.0 and density is 2.20 g/cm3. The length and diameter of the mineral are 10~30 mm and 0.01~0.004 mm respectively, and it dissolves quickly in water, but not in ethanol.The mineral is colourless, biaxial positive and very poor pleochroism in optical properties. The results of index of refraction measured at 22℃isNg=1.480 5,Nm=1.477 5 and Np=1.475 6, and extinction angles 5~10℃. The mass fraction of chemical compositions of Caichengyunite is respectively: FeO,16.15%;Al2O3,7.90%;SO3,33.96%;H2O+,37.64%;H2O-,3.56%; insolubles 0.32% total 99.53%, and it′s calculated formula is Fe32+Al2(SO4)6·30H2O. The strongest diffractive lines of Caichengyunite are 10.468(3,021). 6.494(14,121), 4.886(100,131), 3. 030(9,060), 3.776(21,124), 3.599(3,200), 3.504(9,115), 3.252(13,036), 2.727(12,205) and 1.863(8, 229), and its cell parameters area=0.763 nm,b=2.431 nm,c=2.264 nm and β=111.06°,Z=4.
