Copper pseudomorph after azurite (New Mexico, USA) : 無料・フリー素材/写真
Copper pseudomorph after azurite (New Mexico, USA) / James St. John
| ライセンス | クリエイティブ・コモンズ 表示 2.1 |
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| 説明 | Copper pseudomorph after azurite from New Mexico, USA. (Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, USA)A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties. At its simplest, a mineral is a naturally-occurring solid chemical. Currently, there are over 5500 named and described minerals - about 200 of them are common and about 20 of them are very common. Mineral classification is based on anion chemistry. Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.Elements are fundamental substances of matter - matter that is composed of the same types of atoms. At present, 118 elements are known. Of these, 98 occur naturally on Earth (hydrogen to californium). Most of these occur in rocks & minerals, although some occur in very small, trace amounts. Only some elements occur in their native elemental state as minerals. To find a native element in nature, it must be relatively non-reactive and there must be some concentration process. Metallic, semimetallic (metalloid), and nonmetallic elements are known in their native state as minerals.Copper is the only metallic element that has a "reddish" color - it’s actually a metallic orange color. Most metallic elements, apart from gold & copper, are silvery-gray colored. Copper tends to form sharp-edged, irregular, twisted masses of moderately high density. It is moderately soft, but is extremely difficult to break. It has no cleavage and has a distinctive hackly fracture.The native copper specimen shown above is a pseudomorph - a mineral that has replaced another mineral, but retains the original crystal form. This sample used to be azurite (= Cu3(CO3)2(OH2), copper hydroxy-carbonate). Weathering has produced a thin alteration crust of light green-colored malachite.-------------------Photo gallery of copper:www.mindat.org/gallery.php?min=1209 |
| 撮影日 | 2011-01-30 03:31:57 |
| 撮影者 | James St. John |
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