fibrous pyrite

  • 1Crystal habit — This article is about the descriptive term used in mineralogy. For the addictive drug, see crystal methamphetamine. Pyrite sun (or dollar) in laminated shale matrix. Between tightly spaced layers of shale, the aggregate was forced to grow in a… …

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  • 2Lustre (mineralogy) — Lustre (or luster) is a description of the way light interacts with the surface of a crystal, rock, or mineral. The word lustre traces its origins back to the Latin word lux, meaning light , and generally implies radiance, gloss, or brilliance. A …

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  • 3Mineral — For other uses, see Mineral (disambiguation). An assortment of minerals. A mineral is a naturally occurring …

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  • 4Cone-in-cone structures — in limestone. Cone in cone structures are secondary sedimentary structures that form in association with deeper burial and diagenesis. They consist of concentric inter bedded cones of calcite or more rarely gypsum, siderite or pyrite …

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  • 5coal — coalless, adj. /kohl/, n. 1. a black or dark brown combustible mineral substance consisting of carbonized vegetable matter, used as a fuel. Cf. anthracite, bituminous coal, lignite. 2. a piece of glowing, charred, or burned wood or other… …

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  • 6Limonite — is an ore consisting in a mixture of hydrated iron(III) oxide hydroxide of varying composition. The generic formula is frequently written as FeO(OH)·nH2O, although this is not entirely accurate as limonite often contains a varying amount of oxide …

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  • 7Internal ballistics — Internal ballistics, a subfield of ballistics, is the study of a projectile s behavior from the time its propellant s igniter is initiated until it exits the gun barrel. The study of internal ballistics is important to designers and users of… …

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  • 8marble — marbler, n. /mahr beuhl/, n., adj., v., marbled, marbling. n. 1. metamorphosed limestone, consisting chiefly of recrystallized calcite or dolomite, capable of taking a high polish, occurring in a wide range of colors and variegations and used in… …

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  • 9Marble — /mahr beuhl/, n. Alice, 1913 90, U.S. tennis player. * * * Granular limestone or dolomite that has recrystallized under the influence of heat, pressure, and aqueous solutions. The main mineral in marble is calcite. Commercially, marble includes… …

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  • 10List of minerals — This is a List of minerals for which there are Wikipedia articles. Mineral variety names and mineraloids are to be listed after the valid minerals for each letter.For a complete listing (about 4,000) of all mineral names: List of minerals… …

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