Chinese researchers discover Pacific seabed deposit with record precious metal concentrations

Chinese researchers have discovered a seabed hydrothermal field in the Pacific Ocean containing ores with precious metal concentrations that surpass those found in land-based deposits, according to state media.

The discovery was made during a joint scientific expedition involving several Chinese academic institutions, state broadcaster CCTV reported on Friday.

Exceptional precious metal grades

The ores within the hydrothermal field, an area where hot, mineral-rich water shoots out from openings on the ocean floor, are exceptionally rich in precious metals. Silver reaches more than 1kg (2.2lbs) per tonne of ore at its highest grade, while the average metal content exceeds that of typical terrestrial deposits.

Song Shiji, vice-dean of the Institute for Ocean Engineering at Tsinghua University and one of the lead scientists on the project, said the large seabed mining area "has extremely high exploitation value".

Formation of underwater deposits

These multi-metal deposits form when super-hot, metal-rich water jets out of the seabed and hits near-freezing seawater. The sudden cooling makes the metals bind with sulphur and drop out as solid sulphide minerals, mostly copper, zinc and lead, but often with some gold and silver as well. The survey team noted that the ores are formed when super-hot water shoots from the seabed and are richer in gold and silver than those found on land.

Source: South China Morning Post