An article first published by Bloomberg on June 29 and subsequently reprinted in a number of newspapers around the world has thrown the spotlight on the effect demand for commodities from China and other emerging markets is having on the price of mining tyres. The Bloomberg journalist, Elisabeth Behrmann, compares the price for “tyres about 3.5 metres (11 feet) across,” such as those fitted to Caterpillar trucks employed in for iron ore and coal haulage, are fetching around US$100,000 on the spot market. Behrmann’s figures come from Australian contract miner Leighton Holdings, who works projects for mining majors such as BHP Billiton and Rio Tinto; in reporting the current spot price, she notes it lies above the US price for a Porsche 911 Carrera S or a condominium in Miami. UK buyers, it must be said, have to shell out around 33 per cent more for this particular Porsche model than their American counterparts. But you get the idea.