China has expanded the number of rare earths it will export to the global market, from 10,546 metric tonnes to 21,226 metric tonnes, the country's Ministry of Commerce (MOC) announced on Thursday.

This developed after the Ministry of Environmental Protection approved the export licences of 12 companies that recently passed the required environmental tests.

Of the additional 10,680 metric tonnes, 9,490 metric tonnes were light rare earths, while medium and heavy rare earths were 1,190 metric tonnes, a statement on the MOC Web site said.

China, the world's stronghold of rare earth elements, said in 2011 that Chinese exporters of rare earths elements will be allowed to sell 10,546 metric tonnes of in the first six months of 2012, a 27 per cent reduction from the quota set for the first half of 2011.

Back then, the MOC said the first-round quotas already account for 80 per cent of the full-year volume for 2012, which included 9,095 metric tonnes of light rare earths and 1,451 metric tonnes of heavy rare earths.

But the country had implied it is probable to increase its export quotas on the precious elements pending the approval of environmental inspections of its other rare earths producers.

However, as early as last year, China had made it clear that overall export quotas for the whole of 2012 would remain flat from 2011 to guarantee international market demand and keep rare earth supplies basically stable.

A group of 17 elements, rare earths are metals widely used in high-tech products ranging from flat-screen televisions to lasers and hybrid cars.

Based on earlier calculations by Bloomberg News, China's full-year quota for 2012 may hit about 31,130 metric tonnes.

Beijing imposed an export quota of 30,184 metric tonnes for 2011 and 30,258 metric tonnes in 2010.

China imposed export limits on its rare earths along with other mining products such as silver, minor metals and coke to conserve resources and protect the environment. But this created tensions between China and its trading partners including the U.S., the EU and Japan which claimed the world's second-largest economy practices unfair commerce and currency policies.

The three economic giants ultimately filed a complaint against China before the World Trade Organization in March.

Rare earth deposits exist all over the globe but China is so far the only country that is actively mining and exporting any significant amounts.

Other rare earths players, such as Australian Lynas Corp. and American Molycorp have yet to make its first produce.

Earlier this week, China said it intends to merge its various rare earths producers into one large company and upgrade the sector within two years.

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