Have scientists discovered why China is so rich in rare earth elements the world’s smartphones need?
- Chinese geologists think they have formula that could help to increase control of market in the elements hi-tech industries depend upon
- Simple combination of clay mined for porcelain production, granite bedrock and acid rain could point to lucrative sources of rare earths
China has more than 80 per cent of the world’s reserves of heavy rare earths such as terbium, dysprosium and holmium concentrated in a few provinces to the south of the country.
The reason for the concentration is one of the biggest puzzles in geology, but researchers at the Guangzhou Institute of Geochemistry in Guangdong province say the answer may be found in a combination of clay deposits, acid rain and granite that is distinctive to southern China.
Professor He Hongping and his colleagues came to the conclusion by testing the interaction between rare earths and different types of clay. Through their research they found that kaolinite – or china clay – was the best at absorbing rare earths from water.
The clay, named after Gaoling village near Jingdezhen, a centuries-old ceramic production centre in east China’s Jiangxi province, is a raw material for porcelain production.