Brief Description: The word derives from the ancient Greek word marmaros, which means "shiny stone". The term marble, from a geological point of views, refers only to the grainy (crystallized) limestone and dolomites that have sustained recrystallization under the influence of heat, pressure and water solutions. In the market, however, all the decorative calciferous rocks that can be smoothed and polished, as well as some serpentines, known as green marbles, are referred to as marbles. Marble is a single-mixed rock, consisting only of calcite with granoblastic tissue and it is a product of calcareous recrystallization. Marbles with small percentage of micas are characterized as sipolines. The different varieties of this primitive material are products of calcite sedimentation (a slow process of geological formation) and differ between them in colour, composition, oxidization, as well as the chemical compound. Its hardness, depending on its composition, ranges from 3 to 4, it has an irregular fracture, while its specific gravity varies from 1.8 - 2.8. Marble has the chemical formula of calcium carbonate or calcite (CaCO3) or dolomite (CaMg (CO3)2) or a combination of both minerals. The pure calcite is white, but the various mineral constituents add colour with random standard. For example, the presence of haematite adds red colour. All carbonates, when rained on by acids, produce soluble acids and carbon dioxide. For this reason, acid rain in combination with the atmospheric pollution constitutes the major enemy of marbles. 
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