Monomineral rocks

Monomineral rocks [(calcite (calcium Soil (clay, sand, and organic... 

Marble. The word marble is used as the common name for two types of monomineral rocks one derived from limestone and therefore composed of calcium carbonate, the other derived from dolomite and composed of calcium magnesium carbonate. Extremely high pressures and heat during past geological times modified the structure of both limestone and dolomite, compacting them into a characteristic crystal structure. Most marble is white however, minor and trace amounts of metallic impurities cause the formation of stains in a variety of colors, hues, and patterns, or of colored marble. 

The Bohme s disc method for petrochemical estimation of rocks now used appears to be equivalent to the dynamic abrasion method only for monolithic, monomineral rocks. For rocks softer than silica or those composed of minerals of distinct hardness, porous or partially weathered, no correlation is found between Bohme s method and Vickers hardness or any other hardness, and abrasive action on a surface 42-49 cm2 in area does not allow estimation of the structural and textural specificity of orientations in the rock under test. 

Fig. 8.2. Effects of dynamic abrasion hardness testing of some monomineral rocks.

Stawin J., 1968, IloSciowy pomiar twardosci mineralow i skal monomineralnych (Quantitative measurement of the hardness of minerals and monomineral rocks), Sur. miner., 1. 

Further, to clarify how a dispersion of raw components influence the process of synthesis we studied the impact of differently sized granules of monomineral rock serpentinite and of multimineral dunite. The size of granules varied from 50 to 600 pm. Variation in dispersivity of both rocks altered the yield of the fluorosilicate and the morphology of the crystals. Nevertheless, the effect was stronger expressed in case of serpentinite (Fig. 4). 

Limestone. Limestone usually occurs as a white or light-shaded sedimentary monomineral formed by the consolidation of calcite (composed of calcium carbonate) sediments. It is a soft rock that can easily be cut and shaped into any size and form, so it has been used, since early antiquity, for... 

Much building material has been derived from two monomineral sedimentary rocks gypsum (composed of hydrated calcium sulfate) and limestone, which consists of calcite (composed mostly of calcium carbonate). Freshwater and seawater contain dissolved calcium carbonate and calcium sulfate. Most limestone and gypsum are formed when, as a consequence of the evaporation of water, calcium sulfate and calcium carbonate precipitate out of the water solutions as either gypsum or limestone. Limestone is also formed as a result of the activity of living organisms. Many sea- and freshwater animals, such as snails, clams, and corals, as well as some water plants, draw... 

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