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Djurleite is a copper sulfide mineral of secondary origin with formula Cu31S16 that crystallizes with monoclinic-prismatic symmetry. It is typically massive in form, but does at times develop thin tabular to prismatic crystals. It occurs with other supergene minerals such as chalcocite, covellite and digenite in the enriched zone of copper orebodies. It is a member of the chalcocite group, and very similar to chalcocite, Cu2S, in its composition and properties, but the two minerals can be distinguished from each other by x-ray powder diffraction.〔 Intergrowths and transformations between djurleite, digenite and chalcocite are common.〔Pósfai, M. & Buseck, P. R. (1994): Djurleite, digenite, and chalcocite: Intergrowths and transformations. American Mineralogist, 79, 308-315〕 Many of the reported associations of digenite and djurleite, however, identified by powder diffraction, could be anilite and djurleite, as anilite transforms to digenite during grinding.〔 Djurleite was named for the Swedish chemist Seved Djurle (1928–2000), from the University of Uppsala, Sweden, who first synthesized the mineral in 1958, prior to its discovery in nature. The natural material was first described in 1962 by E H Roseboom Jr, of the US Geological Survey, from occurrences at the type locality, Barranca del Cobre, Chihuahua, Mexico.〔Roseboom, E.H. (1962) Djurleite, Cu1.96S, a new mineral. American Mineralogist: 47: 1181-1184.〕 == The chalcocite group == The chalcocite group is a group of closely related copper sulfides, with the formulae:〔http://rruff.info/ima〕 * Chalcocite (two polymorphs) Cu2S * Djurleite Cu31S16 (Cu1.94S) * Digenite (Cu1.80S) * Roxbyite (Cu1.78S) * Anilite Cu7S4 (Cu1.75S) * Geerite Cu8.5S5 (Cu1.70S) * Spionkopite (Cu1.32S) * Covellite (CuS) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「djurleite」の詳細全文を読む スポンサード リンク
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