More than a third of the houses in the world of made of clay. Clay vessels were instrumental in the invention of cooking, wine and beer making, and international trade. Our toilets are made of clay. The first spark plugs were thrown on the potter's wheel. Clay has played a vital role in the health an beauty fields. Indeed this humble material was key to many advances in civilization. including the developement of agriculture and the invention of baking, architecture, religion and even the space program.