White Marble in India – Supplier http://www.tripurastones.in/query.php White Marble has grey form in it because of impurities. But these impurities form a design in the white marble and make it more beautiful. Before metamorphism process, the calcite in the limestone is in the form of fossil material and biological debris. During metamorphism process, this calcite rock re-crystallizes and the texture of the rock changes. In the early stages of metamorphism process of the limestone-to-marble transformation, the calcite crystals in the rock are very small to become a rock.