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Népouite is a rare nickel silicate mineral which has the apple green colour typical of such compounds. It was named by E Glasser in 1907 after the place where it was first described (the type locality), the Népoui Mine, Népoui, Nouméa Commune, Northern Province, New Caledonia. The ideal formula is Ni(SiO)(OH), but most specimens contain some magnesium, and (Ni,Mg)(SiO)(OH) is more realistic. There is a similar mineral called lizardite in which all the nickel is replaced by magnesium, formula Mg(SiO)(OH).〔http://www.mindat.org/min-8771.html〕 These two minerals form a series, that is to say intermediate compositions are possible, with varying proportions of nickel to magnesium.〔American Mineralogist (1975): 60: 863-871〕 Pecoraite is another rare mineral with the same chemical formula as népouite, but a different structure; such minerals are said to be dimorphs of each other, in the same way as graphite is a dimorph of diamond. Népouite, lizardite and pecoraite are all members of the kaolinite-serpentine group.〔Dana’s New Mineralogy, Eighth Edition, 1997, Gaines et al., Wiley.〕 Garnierite is a green nickel ore that formed as a result of weathering of ultramafic rocks, and that occurs in many nickel deposits worldwide. It is a mixture of various nickel and magnesium phyllosilicates (sheet silicates), including népouite. Associated minerals include calcite, chlorite, goethite, halloysite, nontronite, pimelite, quartz, sepiolite, serpentine, talc and willemseite. As well as the type locality in New Caledonia, it has been found in Australia, Austria, the Czech Republic, the Democratic Republic of Congo, Germany, Greece, Italy, Japan, Morocco,〔Mineralogical Record 38-5, page 384〕 Poland, Russia, South Africa and the USA. ==Structure== Space Group Ccm21. Unit Cell: a = 5.31 Å, b = 9.19 Å, c = 14.50 Å 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「Népouite」の詳細全文を読む スポンサード リンク
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