Nautilus Minerals’ wholly-owned subsidiary, Tonga Offshore Mining Limited (TOML), has upgraded its mineral resource estimate for the Clarion-Clipperton Fracture Zone (CCZ) in the Central Pacific Ocean, not far from Tonga.

The estimate for the polymetallic nodule project includes portions in the inferred, indicated and measured categories. It follows the successful completion of exploration campaigns in the CCZ in 2013 and late 2015.

Nautilus’ CEO Mike Johnston said, “It is exciting to announce this increase in the CCZ project’s inferred mineral resource base from 410 million tonnes (wet) to 685 million tonnes (wet) as well the upgrade of an additional 68 million tonnes (wet) into the indicated category and 2.6 million tonnes into the measured category.”

The estimate at an abundance cut-off of 6 wet kg per square metre is the selected base case scenario considering a non-selective bulk mining operation.

Mike Johnston said, ‘Our updated mineral resource for the CCZ highlights again the significant potential of seafloor resources. Technological advances in mining, oil & gas and maritime technologies over the last 20 years now mean there are reasonable prospects for economic extraction of these massive mineralized systems.

“At Nautilus, we are both excited and privileged to be leading the development of this significant, currently untapped potential, first with our high grade Solwara 1 Seafloor Massive Sulphide (SMS) Project in Papua New Guinea, and other SMS systems in the South West Pacific, and now with this updated polymetallic nodule mineral resource in the CCZ.”