Even today, the uses of this ancient medium are vast. In some instances clay is both the beginning and finished work, but in the world of art, it is also used as a creative medium to help build the shape in the mind in preparation of using a more difficult medium, working as a transitional material. Even Michelangelo, in his maturity, made full-scale clay models of his work before carving it in stone. Clay is found in abundance in the earth near rivers, wetlands and hills. There are several types of clay that can be used.
Kaolin is a fine white clay used to create porcelain.
Terre-cotta is a wet molding clay. Terre-cotta and stoneware are chiefly used by sculptures. These clays are all natural, have a water base, and dry to various levels of hardness. Plastelene, an oily synthetic clay, is used by many sculptures and has the advantage of not drying but does not have the flexibility of wet clay. Clay can be purchased in various forms, but can also be dug directly from the ground.