Il Australian minister of resources (given the importance of the mining sector in Australia there is a special minister) recently declared that the minerals/metals boom it's over. “It's not finished because it never was,” he replied Tom Albanese, the head of Rio Tinto, one of the world's largest mining companies. The recent weakness in those commodity prices basically reflects the Chinese slowdown, and Albanese essentially gives a political cause: “The Chinese leadership had given us clear signals that with the approach of the exchange rate at the top there would be a period of 'calm' in growth. But then, with a new summit that will want to give a signal of confidence, the levers of economic policy will be used to restart the Chinese giant".
In any case, the weakness of the prices also depends, as in the classic 'hog cycle', on the response of the offer to the solicitations of the demand. For example, in the case of coal, Chinese imports from Mongolia, where a huge deposit has come into production, have now overtaken imports from Australia.
http://www.smh.com.au/business/big-miners-bust-boom-myth-back-longterm-growth-20120823-24p2z.html
http://www.smh.com.au/business/china-lines-up-supplies-much-closer-to-home-20120823-24oyf.html
