Scrap metal forms a major part of all household and industrial waste. High commodity prices since the early 2000s have made its trade a lucrative business for dealers of all sizes. Different scrap metals are divided into two broad categories: ferrous metals that contain iron, such as various steel grades, and non-ferrous metals that can be copper, aluminium, nickel, and lead.
There are two categories of ferrous scrap: heavy iron and light iron. The heavy variety includes objects like vehicle chassis, cast iron radiators, and forklift trucks. This category also includes bulkheads and other steel components of aircraft, ships, and trains. Light iron scrap objects are the steel casings of electrical appliances such as washing machines, fridges, lawnmowers, microwave ovens, and computer towers.
Copper is a valuable and widely traded non-ferrous metal. Copper electric wiring, heavy duty electric cables, hot water tanks and copper plumbing, are items always in high demand. Secondary copper scrap includes copper coils and other parts from engines, air conditioning compressors, and transformers. Copper alloys in ornaments, electronic gadgets, and some electric coils contain recoverable amounts of nickel, zinc, cobalt, and titanium.
Scrap aluminium is valuable as its recycling uses only a fraction of the energy required for smelting during its primary production. Aluminium scrap consists of old window and door frames, radiators, vehicle bodywork, road signs, food and beverage cans, saucepans, and other household utensils. Aluminium foil and foil trays make up a large part of British household scrap after the Christmas festive season.
In Britain, lead traditionally has been used for roofing seals, plumbing, and drain covers. Theft in all of these items from residential, industrial, and church premises escalated after the early 2000s with the rise in world metal prices. Electrical appliances and batteries contain commercially recoverable amounts of lead.