This set is used to crush, grind, and mix solid substances. The pestle is a heavy bat-shaped object, the wide-end of which is used for crushing and grinding. The mortar is a bowl, typically made of hard wood, ceramic or stone. Sometimes referred to as an "Apothecary Grinder" by individuals unfamiliar with its use, the proper historical name is "mortar and pestle". Mortars are used in cooking to prepare ingredients such as guacamole, gazpacho and pesto (which derives its name from the pestle pounding), as well as grinding spices into powder.