Mankind uses about 32 billion tons of mineral and energy resources every year. There are 5 main categories: building materials, industrial materials, metals, energy minerals and precious substances.
These resources are spread very unequally throughout the world. Some minerals are relatively common, like iron – the most mined mineral in the world. Its production reached 1.6 billion tons in 2006 and is currently increasing by 10 % a year. The three largest producers are, in order, China, Brazil and Australia. Other minerals are rarer, like hafnium, which is used to make filaments and electrodes. The world stocks are estimated at 1 million tons in total (most of this is in South Africa).
Open air or underground mines
There are different types of mines. An open air mine is a huge basin with rows that are dug by layers of rock being successively scraped. A recent technique which causes many problems is called Mountain top...