Much used for sculpture, marble is a metamorphic rock, that is one that has been subjected to great heat and changed its crystalline structure in the process. White marble has been quarried in many parts of the world, but the most famous is that from Carrara in the Apuan Alps in Italy. It was used in antiquity and much favoured in the renaissance, especially by Michelangelo. The neoclassical sculptor Antonio Canova (1757–1822) was also attracted by its purity. Many forms of hard limestone are incorrectly termed marbles.