单词 | bismuthinite |
释义 | bismuthinitebismuthinite(bɪzˈmʌθɪˌnaɪt) orbismuth glanceBismuthinitebismuthinite[′biz·məth·ə‚nīt]Bismuthinite(also called bismuth glance), a mineral belonging to the sulfide compounds. Chemical composition, Bi2S3 (81.30 percent Bi, 18.70 percent S), sometimes with admixtures of lead, copper, iron, arsenic, antimony, and other metals. It crystallizes in a rhombic system. The structure consists of linked Bi-S-Bi chains along the C axis. It normally forms acicular crystals, lamellae, radial growths, and fibrous or granular aggregates. It is opaque and silvery-white, with a metallic luster. It tarnishes and becomes covered with a gray film when exposed to air. Its hardness is 2-2.5 on the mineralogical scale, and its density is 6,780-6,810 kg per cu m. Bismuthinite is formed in hydrothermal, greisen and contact-metasomatic deposits together with arsenopyrite; sulfides of Zn, Pb, Cu, and Fe; and minerals of tin, tungsten and molybdenum, native bismuth, and others. In a zone of oxidation it breaks down slightly and forms secondary oxides (bismite), sulfoxides, and aqueous bismuth carbonates. Bismuthinite is the main mineral from which bismuth is extracted. G. P. BARSANOV |
随便看 |
|
英语词典包含2567994条英英释义在线翻译词条,基本涵盖了全部常用单词的英英翻译及用法,是英语学习的有利工具。