tantalite
enUKtan·ta·lite
T0039800 (tăn′tə-līt′)tantalite
(ˈtæntəˌlaɪt)tan•ta•lite
(ˈtæn tlˌaɪt)n.
| Noun | 1. | tantalite - a mineral consisting of tantalum oxide of iron and manganese that occurs with niobite or in coarse granite; an ore of tantalum |
| 单词 | tantalite | |||
| 释义 | tantaliteenUKtan·ta·liteT0039800 (tăn′tə-līt′)tantalite(ˈtæntəˌlaɪt)tan•ta•lite(ˈtæn tlˌaɪt)n.
TantaliteenUKtantalite[′tant·əl‚līt]Tantalitea mineral of the group of multiple oxides; the extreme member of the isomorphic columbite-tantalite series. Its chemical composition is (Fe,Mn) (Ta,Nb)2O6. In tantalite, tantalum predominates over niobium in percent by weight. Varieties of tantalite are ferrotantalite, in which FeO: MnO > 3:1 and the FeO content reaches 14 percent, and manganotantalite, in which MnO:FeO > 3:1 and the MnO content reaches 14 percent. Ca, Mg, Sn, Ti, W, U, and Th are present as admixtures. Tantalite crystallizes in the orthorhombic system; it is of the columbite structural type. The crystals are tabular and acicular and the colors are black, grayish, brown, and red-brown. In the columbite-tantalite series, there is a regular change in physical properties with increasing Ta205 content; tantalite is harder (up to 6.5 on Mohs’ scale) and denser (7,000–8,200 kg/m3). Tantalite differs from columbite in its optical constants in the infrared region of the spectrum. Tantalite is genetically associated with granites, rare-metal, muscovite, and quartz-feldspar pegmatites, carbonatites, and alkaline rocks. In pegmatites, tantalite crystallizes in a later stage than columbite, associating with albite, lepidolite, beryl, and other minerals. Tantalite is resistant to weathering and concentrates in placers, which are the main source for its extraction. It is used as an ore of tantalum. tantaliteenUK
Words related to tantalite
|
|||
| 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。