Established in 1958, Active Brass Foundry is a private company located in Telford, Pennsylvania. The foundry is a factory that produces metal castings. Metals are cast into shapes by melting them into a liquid, pouring the metal in a mold, and removing the mold material or casting after the metal has solidified as it cools. The most common metals used to produce metal castings are aluminum, iron, steel, magnesium, copper, tin, and zinc. Other processes include: molding sand castings which are produced by mixing virgin silica sand with clay or organic chemical binders. The most widely used sand binders are bentonite clays (sodium bentonite and calcium bentonite), and these molding sands are known as green sands.