The “super-cycle” theory, which predicts an extended period of expensive raw materials on the back of the industrialisation and urbanisation of emerging economies such as China and India, is back with a vengeance.
The ups and downs of the global economy are masking some of the movements, but over the first months of 2010, the price of some of the world's top commodities leapt: oil prices rose towards $80 a barrel and iron ore surged close to an all-time high; only wheat and rice remained relatively low.
Prices are suffering now because of concerns about the impact on global economic growth of Europe's sovereign debt problems and China's efforts to cool house prices.