For a continent that gets much of its foreign exchange from the export of raw materials, it is surprising how small Africa's mining sector still is today on a global scale: just 10% of the world's production.

In an October report on trends in the mining industry, the International Council on Mining and Metals (ICMM) said that the value of the world's mining sector has tripled in the last decade, from $214bn in 2000 to $644bn in 2010.

Of this, 71% of the total value is dominated by four minerals – iron ore, copper, gold and nickel – all present in Africa.

The ICMM says that 84% of the total future project pipeline is based on these four minerals. In 2011, Africa had $99bn worth of investment in the pipeline, 15% of the global total.

However, debates rage between those who argue Africa's mineral potential has been underexplored and those who believe exploitable resources are quickly disappearing●

00: investment ($bn) 17 00: global share (%)