The bowls of tobacco pipes are commonly made of briar wood, meerschaum, corncob, pear-wood, rose-wood or clay. Less common are other dense-grained woods such as cherry, olive, maple, mesquite, oak, and bog-wood. Minerals such as catlinite and soapstone have also been used. Pipe bowls are sometimes decorated by carving, and moulded clay pipes often had simple decoration in the mould