In metalworking and jewellery making, casting is a process in which a liquid metal is somehow delivered into a mold (usually by a crucible) that contains a negative impression (i.e., a 3-dimensional negative image) of the intended shape. The metal is poured into the mold through a hollow channel called a sprue. The metal and mold are then cooled, and the metal part (the casting) is extracted. Casting is most often used for making complex shapes that would be difficult or uneconomical to make by other methods.
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