Marble, is a metamorphic carbonate rock formed by recrystallization of limestone, so that the texture of limestone has metamorphosed over time under pressure and heat, it recrystallizes and forms a large, coarse-grained calcite. The rock has a distinctive crystalline texture and is mainly composed of calcite and dolomite minerals, or a combination of them. Its apparent difference with the travertine that can be empirically observed is that if you look at the back of stone, you will find that marble unlike travertine has no pores.