BEIJING - China's export of rare earth metals burst through the $100,000-a-ton mark for the first time in February. That's an almost ninefold increase from a year before, while the volume of trade stayed far below historical averages.

China's quota policy on rare earths, which are used in a wide range of hardware including precision-guided weapons, hybrid car batteries and iPads, has forced prices up dramatically since July last year, when each ton fetched a mere $14,405 on average.

The apparent price rises have averaged $10,000 monthly for each ton. They accelerated in February, galloping ahead by $34,000 for each ton, according to Reuters calculations based on data from China's Customs office.