containing rare metals found off eastern Japan
A team led by Japan's marine science agency said Monday it has
found rocks containing cobalt and other rare metals on the Pacific
seafloor off eastern Japan, in an area covering around 950 square
kilometers, about half the size of Tokyo.
Rare metals are widely used in high-tech products. As Japan
relies largely on imports, extracting mineral resources from its
waters would help to stabilize supply of rare metals.
Using its Kaiko remotely operated research vehicle, the Japan
Agency for Marine-Earth Science and Technology surveyed a seamount
350 km off the Boso Peninsula in Chiba Prefecture in April with
Ibaraki University and two other universities, confirming cobalt-rich
crusts covering a mountain ridge at depths ranging from 1,500 to
Based on the survey, the seamount is believed to be fully
covered in such crusts. The team also collected samples from crusts
as thick as 13 centimeters at a depth of 3,200 meters.
The team also found cobalt-rich deposits last year off
Minamitori Island, Japan's easternmost territory.
Katsuhiko Suzuki, an agency researcher, hailed the latest
findings as "significant" because the rocks were found at a
relatively accessible location, enabling the team to more easily
study how the crusts were formed and their distribution.
Cobalt-rich crusts contain not only cobalt, but also nickel,
platinum and other minerals. (June 5)