is a hard crystalline metamorphic
form of limestone
, typically white with mottlings or streaks of color, that is capable of taking a polish and is used in sculpture and architecture. Calcite is the principal mineral that composes marble. Shades of marble cover a broad span including white, black, grey, red, yellow, pink, and green. The colors are often positioned in bands which creates the beautiful look associated with finished marble. The range of colors is due in large part to impurities like sand, iron, clay, silt, etc. Some of the more well known areas for marble include Greece, Turkey, Spain, Italy, Belgium, and the United States.