Kazakh geologists have discovered a rare earth metal deposit with estimated resources of more than 20 million metric tons at a depth of up to 300 metres, the country's industry and construction ministry said in a statement on Wednesday.

Kazakhstan does not currently feature in the U.S. Geological Survey's list of countries by rare earth metal deposits. If confirmed, the deposit would place Kazakhstan behind only China and Brazil by size of reserves.

In a statement on Telegram, the ministry said that the Zhana Kazakhstan site, which is 420 km (261 miles) from the country's capital, contained neodymium, cerium, lanthanum and yttrium, and that its average rare earth metal content is 700 grams per ton.

It did not specify which companies may develop the site, or when.