China will step up its controls over the mining of rare earths and release new industry standards to cut pollution, a minister and media said on Friday, after the world’s biggest supplier cut export quotas for the minerals.

China, which produces about 97 percent of the global supply of the vital metals, slashed its export quota by 35 percent for the first half of 2011 compared with a year earlier, saying it wanted to conserve reserves and protect the environment.

China will “strengthen the supervision and management of mineral resources mining … and deepen control over rare earth mining capacity and extraction,” Minister of Land and Resources Xu Shaoshi said on a webcast on the ministry’s website (www.mlr.gov.cn). He did not elaborate.