Calcium Carbonate, is one of the
commonest mineral combination to be found on Earth. It is
estimated that the mineral accounts for as much as 14% of the
Earth's crust and is formed in many different geological
environments. Calcite can form rocks of considerable mass and
constitutes a significant part of all three major rock
classification types. From the mineralogical point of view,
calcium carbonate falls into three structurally different groups:
the calcite group, the aragonite group, and the dolomite group.
Limestone is generally used as a generic term which
designates a compacted sedimentary rock made of calcium carbonate.
It is often used as a synonym for natural calcium carbonate.
Marble is a metamorphic rock, which is the result of a
re-crystallization process of limestone, under conditions of high
pressure and temperature. True marble has a low porosity and may host
calcite crystals of several centimeters.
All these minerals, when of the highest quality, are the source of
industrial calcium carbonate.
The following graph gives some estimates of the calcium carbonate
consumption by industry: