Prices of rare earths have skyrocketed this year as China moves to consolidate the sector in order to tighten its grip over the highly coveted minerals used in high-tech products, analysts said Monday.

Prices of heavy rare earths, which are more expensive than the light elements due to their scarcity, have soared by up to five times since the start of 2011, Zhang Fang, an analyst with China Securities Co Ltd, told AFP.

Those of light rare earths have meanwhile jumped by two to three times during the same period, she said.

Europium oxide, which is used to make television sets and fluorescent lamps, cost 26,000-28,000 yuan ($4,015-$4,324) per kilo on Monday, up from 7,700-8,200 yuan a month ago, according to industry website Shanghai Metals Market.

China produces more than 95 percent of the world's rare earths -- 17 elements critical to making everything from iPods to electric cars and missiles -- and Beijing has been trying to bring the minerals under state control.

The price surge was "mainly led by government policies that support industry consolidation", Zhang said.

"Both domestic and foreign demand are currently still quite strong," she said, adding speculation may have also played a part in driving up prices.

China has taken a series of measures to tighten control over the industry, citing environmental concerns and domestic demand -- moves that have triggered complaints from foreign buyers.

The State Council, or cabinet, said last month it wanted to consolidate the rare earths sector to allow the biggest producers to dominate the industry within two years.

In January, Beijing announced it had brought 11 rare earth mines in the eastern province of Jiangxi, which is rich in heavy rare earths, under state control.

Earlier this month, the local government of Inner Mongolia said state-owned Baotou Iron and Steel (Group) would take over rival processors in the region, effectively creating a monopoly in the upstream industry in north China.

In an indication of a potential further supply crunch, the State Council last month announced for the first time that it planned to build national reserves for rare earths.

Baotou Iron and Steel (Group) had been building commercial reserves with total capacity of more than 200,000 tonnes, roughly twice China's annual production, Chinese media reports said earlier.

Beijing has cut rare earths exports for the first half of 2011 by 35 percent compared with a year earlier, having slashed the quota by 72 percent for the second half of last year.

It has also set tougher environmental standards for the industry, restricted production capacity in projects that separate rare earths from crude ores, and raised taxes.