It has been a banner year for fossil-fuel, metals and agricultural markets. For many commodity traders, the boom in prices has had an unexpected effect: a credit crunch that is reshaping the industry in favor of the largest players.
Higher prices are requiring traders to borrow more money to finance the same volume of oil, copper or coffee. In some instances, extreme or unusual weather is causing gyrations in commodity prices, prompting traders to amass cash in a pinch.
