The foundry is an establishment that produces metal objects, called castings, by pouring molten metal into a hollow mold, usually made of sand. The liquefied metal is then allowed to solidify. In the making of sand molds, suitable mixtures of molding sand are rammed around patterns that are removed after the impression has been produced.

The first operating iron works in the US was established in Massachusetts in 1643, even though the process itself dates to prehistoric times. The early blast furnaces in America used ores from nearby sources and charcoal for fuel. The metal from these furnaces was poured directly into molds for stove plates, kettles, andirons, baking pans, and other household items.

Although foundry-made castings have been supplanted to some extent today by other methods and materials, the foundry continues to be a major source for some heavy metal objects, such as car engine blocks.