An ingot is a piece of relatively pure material, usually metal, that is cast into a shape suitable for further processing. In steelmaking, it is the first step among semi-finished casting products. Ingots usually require a second procedure of shaping, such as cold/hot working, cutting, or milling to produce a useful final product. Non-metallic and semiconductor materials prepared in bulk form may also be referred to as ingots, particularly when cast by mold based methods. Precious metal ingots can be used as currency, or as a currency reserve, as with gold bars.
Aluminium ingot after ejection from mold
Pouring molten gold into a mold at the La Luz Gold Mine in Siuna, Nicaragua, about 1959.
Pouring ingots at a steel mill
Re-melted tin affected with tin pest is poured into ingot molds at Rock Island Arsenal Joint Manufacturing and Technology Center, Rock Island, Illinois.
Precious metals are rare, naturally occurring metallic chemical elements of high economic value. Precious metals, particularly the noble metals, are more corrosion resistant and less chemically reactive than most elements. They are usually ductile and have a high lustre. Historically, precious metals were important as currency but are now regarded mainly as investment and industrial raw materials. Gold, silver, platinum, and palladium each have an ISO 4217 currency code.
Gold nugget
1,000 oz silver bar
500 g silver bullion bar produced by Johnson Matthey
1 oz Vienna Philharmonic gold coin