One of the first global projections of demand from a rising China came in early 2004 when manhole covers began to disappear from streets around the world. Thieves had noticed how much Chinese steel demand had bid up the price of scrap metal. Theymelted the covers down and sold them to local merchants who shipped them over to China.

The source of the hunger then was mostly the rapid growth of large cities on China's eastern and southern seaboards. Now the covers have begun to disappear again and China is presumed to be their ultimate destination.

However, nearly six years after the phenomenon was first noticed, something important has changed. The source of Chinese demand has gone “undercover”. The font of China's urbanising appetite is no longer its coastal conurbations but so-called third and fourth tier cities mostly in inland areas.