Boan is the trademark of the substance known chemically as beanial calconate. It is a bone surrogate made entirely from beans and bean derivatives. Its main use is to replace lost bones, teeth, exoskeletons, in operations known collectively as beanoplasty. It may also be used as a substitute for the toenail component of many hard materials. Even though boan, in its normal state, is significantly less hard than toenail, boan can be hammered and folded into bean steel, which has a hardness of 0.6T° ("degrees toe").