Cast iron
Cast iron is made from pig iron, which is the product of smelting iron ore in a blast furnace. Cast iron can be made directly from the molten pig iron or by re-melting pig iron, often along with substantial quantities of iron, steel, limestone, carbon (coke) and taking various steps to remove undesirable contaminants. Phosphorus and sulfur may be burnt out of the molten iron, but this also burns out the carbon, which must be replaced. Depending on the application, carbon and silicon content are adjusted to the desired levels, which may be anywhere from 2–3.5% and 1–3%, respectively. If desired, other elements are then added to the melt before the final form is produced by casting.
Metal furniture
Cast Iron is used mainly for outdoor finishings and settings, such as those used for bench legs and solid iron tables. It is suited to outdoor use due to its hardness, heaviness and general tough composition. The main disadvantage to this is that it, being a relatively pure form of Iron is subject to corrosion at the hands of the moisture and air.