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fair on | fracture = Subconchoidal to uneven | mohs = 3.5–4.0 | luster = Adamantine to vitreous; silky if fibrous; dull to earthy if massive | refractive = nα = 1.655 nβ = 1.875 nγ = 1.909 | opticalprop = Biaxial (–) | birefringence = δ = 0.254 | pleochroism = | streak = light green | gravity = 3.6–4 | melt = | fusibility = | diagnostic = | solubility = | diaphaneity = Translucent to opaque | other = | references = 〔(Malachite in Handbook of Mineralogy )〕〔(Malachite at Webmineral )〕〔(Malachite at Mindat )〕 }} Malachite is a copper carbonate hydroxide mineral, with the formula Cu2CO3(OH)2. This opaque, green banded mineral crystallizes in the monoclinic crystal system, and most often forms botryoidal, fibrous, or stalagmitic masses, in fractures and spaces, deep underground, where the water table and hydrothermal fluids provide the means for chemical precipitation. Individual crystals are rare but do occur as slender to acicular prisms. Pseudomorphs after more tabular or blocky azurite crystals also occur.〔 ==Etymology and history== The stone's name derives (via Latin: ''molochītis'', Middle French: ''melochite,'' and Middle English ''melochites'') from Greek ''Μολοχίτης λίθος'' ''molochitis lithos'', "mallow-green stone", from ''μολόχη'' ''molōchē'', variant of ''μαλάχη'' ''malāchē'', "mallow".〔(Malachite ), Dictionary.com〕 The mineral was given this name due to its resemblance to the leaves of the Mallow plant. Archeological evidence indicates that the mineral has been mined and smelted to obtain copper at Timna Valley in Israel for over 3,000 years.〔Parr, Peter J review of "Timma: Valley of the Biblical Copper Mines" by Beno Rothenberg Bulletin of the School of Oriental and African Studies, University of London, Vol. 37, No. 1, In Memory of W. H. Whiteley (1974), pp. 223–224〕 Since then, malachite has been used as both an ornamental stone and as a gemstone. 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「malachite」の詳細全文を読む スポンサード リンク
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