Deep sea mining test set

Japan embarks Sunday on what it says is the world’s first bid to tap deep sea rare earths at a depth of 6,000 meters — greater than the height of Mount Fuji — to curb dependence on China.

A Japanese deep-sea scientific drilling boat called the Chikyu will set sail for the remote island of Minami Torishima in the Pacific, where surrounding waters are believed to contain a rich trove of valuable minerals.

The Japan Agency for Marine-Earth Science and Technology touted the test as the world’s first at such depths.

The area around Minami Torishima, which is in Japan’s economic waters, is estimated to contain more than 16 million tons of rare earths, which the Nikkei business daily says is the third-largest reserve globally.

These rich deposits contain an estimated 730 years’ worth of dysprosium, used in high-strength magnets in phones and electric cars, and 780 years’ worth of yttrium, used in lasers, Nikkei said.