According to Bloomberg News, a shortage of nickel drove prices to the highest level since at least 1987, and forced the London Metal Exchange to impose trading restrictions for the first time in a year.

"After nickel surpassed $29,000 a metric ton, twice its level at the start of this year, the exchange ordered the suspension of rules for delivery of the metal. Inventories have plunged 83 percent in the past year. The price of nickel [used to make steel rust-resistant] is four times higher than the average of the 1990's because of a surge in demand from China."