China discovers vast gold and silver 'mine' in the Pacific with unheard-of deposits

Chinese scientists have discovered a mineral deposit containing a large amount of gold and silver in the Pacific Ocean. The high concentration of the two metals is an extremely unusual find. The researchers said that the region has huge economic value and mining potential, CCTCV News reported. However, mining the ocean floor remains a contentious topic.

A joint scientific expedition carried out by researchers from Tsinghua University, the Qingdao Institute of Marine Geology and Shanghai Jiao Tong University made the discovery. The gold and silver deposits were found in a hydrothermal field, an area on the ocean floor where extremely hot fluids rich in minerals seep upwards through the cracks.

Sulfide cones with huge amounts of gold and silver

The team found three large, cone-shaped seafloor massive sulfides (SMS) or hydrothermal sulfide deposits. Most of the time, they contain copper, zinc and lead, and smaller quantities of gold and silver. In this case, they found that the precious metals surpassed the rest. CCTV News reported that the gold and silver deposits in some of the ore samples exceed those found on land.

How much gold and silver was discovered by China?

According to preliminary analysis, gold concentrations reach up to 0.45 troy ounces (0.4937 ounces) per US short ton of ore, while silver grades reached 36.3 troy ounces (39.83 ounces) per US short ton. The potential polymetallic sulfide resources in the area could be equal to world-class seafloor deposits. "The [large seabed mining area] has extremely high exploitation value," said Song Shiji, one of the lead scientists on the project.

The expedition and research

The 18-day voyage started from Shenzhen on August 10 on the Chinese oceanographic research ship Xiang Yang Hong 10. The researchers conducted seven dives with submersibles during this time, which led them to a back-arc basin in the western Pacific. Previous expeditions had already identified dozens of hydrothermal vents at depths between 2,300 and 4,920 feet, with temperatures reaching more than 315 degrees Celsius. Later, they came across a very large hydrothermal mining area within the basin.

After they came across the mounds, the ore bodies were analysed in the laboratory on the ship, which showed that they are mainly composed of chalcopyrite, pyrite and sphalerite, minerals with high economic value. Some of the samples contained 15.4 parts per million (ppm), equivalent to 15.4g of gold per ton of ore, while silver content reached as high as 1,271 ppm, or 1,271g per ton.

Location of gold and silver deposits

According to maritime tracking data, Xiang Yang Hong 10 travelled through waters north and east of Taiwan and north of the Philippines during the expedition. Chinese state media reported that the basin is located within China’s exclusive economic zone, although the exact coordinates have not been shared.