Marmi

texture selection for rendering

Marble is a metamorphic rock composed predominantly of calcium carbonate. (CaCO3).
The word marble derives from the ancient Greek μάρμαρον (mármaron) or μάρμαρος (mármaros), meaning "shining stone", in turn derived from the verb μαρμαίρω (marmàirō), meaning "to shine, to sparkle"

Marble is formed through a metamorphic process from sedimentary rocks, such as limestone or dolomite, which causes a complete recrystallization of the calcium carbonate of which they are mainly composed and gives rise to a mosaic of calcite or dolomite (mineral) crystals. The combined action of temperature and pressure, during the transformation of the sedimentary rock into marble, leads to the progressive obliteration of the structures and textures originally present in the rock, with the consequent destruction of any fossils, stratifications or other sedimentary structures present in the original rock.

The color of marble depends on the presence of mineral impurities (clay, silt, sand, iron oxides, flint nodules), existing in granules or layers within the original sedimentary rock. During the metamorphic process, these impurities are moved and recrystallized due to pressure and heat. White marbles are the result of the metamorphosis of calcareous rocks free of impurities.....Wikipedia...>>