In trading, metals are a tradable commodity.
The traded groups of metals include precious (gold, silver and platinum group metals - platinum, palladium, rhodium), base (aluminium, copper, zinc, nickel, lead, tin, aluminium alloy, cobalt, molybdenum) and ferrous metals (hot and cold rolled coil, billet, iron ore).
The World Bank reports that China was the top importer of ores and metals in 2005 followed by the United States and Japan. Big producers and exporters include Brasil, Australia and South Africa.
China is also the world’s largest copper consumer, accounting for almost 40% of world consumption in 2014. That is why negative economic data from China usually weighs on copper.