It should be a chance to jump at. The attempt by Vale, the Brazilian mining giant, to buy Xstrata, its Anglo-Swiss rival, would create the world’s biggest mining company. It would also be a giant step in Vale’s strategy to become a fully diversified global mining group at a time when demand for industrial commodities, above all from China, is buoyant.

Yet the Chinese themselves may derail it. Following the dawn raid by Chinalco and Alcoa on Rio Tinto that may scotch a takeover bid from BHP Billiton, rumours were circulating at the weekend that Chinalco’s backers at the China Development Bank may be preparing to take a stake in Glencore, Xstrata’s biggest shareholder. This could easily scupper the Vale deal.