Marble Calcite Limestone
The variety of colours exhibited by marble are a consequence of minor amounts of impurities being incorporated with the calcite.
Marble calcite limestone. The calcite in the limestone changes and fossils and layering in the original limestone disappear as interlocking grains grow. Form of it when limestone buried deep in the older layers of earth s crust is subjected to heat and pressure from thick layers of overlying sediments. Marble is a metamorphic rock formed by the alteration of limestone by heat and pressure. When the heat and pressure hits the limestone calcite seed crystals form.
With continued metamorphism these crystal seeds grow while any clay deposits in the limestone transform into silicate structures such as mica. If the limestone is pure a white marble is formed. Marble is a granular metamorphic rock it is derived from limestone or dolomite and it consists of a mass of interlocking grains of calcite or the mineral dolomite. Limestones may include layers of clay or sand which may form the attractive flow banding and colours found in decorative marble.
The calcite in the limestone changes and fossils and layering in the original limestone disappear as interlocking grains grow. Because marble is a fairly soft material only a three on the mohs hardness scale it is easy to cut and carve. Marble is a metamorphic rock formed when limestone is exposed to high temperatures and pressures. If the limestone is pure a white marble is formed.