Marble

Marble is a metamorphic limestone. When limestone is heated and has pressure put on it, its calcite is melted. Larger crystals are formed and this is marble. Whatever is mixed in with the limestone decides the final color of the marble. If limestone is pure, you get a white marble. If it has hematite or clay in it, you will get a reddish color marble. Most marble is large grained and comes in many colors and patterns.