Metal casting is a process whereby molten metal is poured into a mold shaped like the desired finished product. The cast metal remains in the mold until it has solidified. Single molds produce only metal casting and are typically used for small productions runs. Multiple use molds are used for large production runs of metal castings. Multi-use molds are more expensive, but will withstand repeated use. The type mold to be used for metal casting is dependent upon the finished product. For example, some molds are capable of producing more intricate metal casting parts than others and some can produce parts more economically, while some molds can produce only one metal casting, and others can produce many metal castings from a single mold.