Jervois Mining (ASX:JRV, JRV.V) has released an updated resource estimate in January where an additional 19 hole drill program (for a total of just over 3,100 meters drilled) which helped the company to improve the modelling exercise for the deposit which contains narrow high-grade areas of mineralization.
Whereas the 2018 resource estimate contained 3.87 million tonnes of rock in the measured and indicated categories at 0.59% cobalt and 0.85% copper, the updated resource estimate now contains a higher tonnage at a lower average grade: using the same 0.20% Co cutoff grade, the measured and indicated resources in the most recent resource update contain 4.7 million tonnes at 0.49% cobalt and 0.74% copper. Despite the lower grade, the higher amount of tonnes results in a virtually unchanged amount of cobalt in the ground (46.3 million pounds versus 45.7 million pounds) and a slightly higher copper and gold resource 70.2M lbs and 82,000 ounces versus 65.8M lbs and 68,000 ounces respectively). Interestingly, the cutoff grade of 0.20% was based on just the cobalt content and no gold or copper values have been included in the calculation to determine the cutoff grade.
If one would lower the cutoff grade to 0.15% cobalt, the measured and indicated resource would increase even further to 5.77 million tonnes while the grade drops to 0.44% cobalt and 0.69% copper for 50.1 million pounds of cobalt and 80.1 million pounds of copper.
This resource update will now be the basis for the bankable feasibility study of the Idaho Cobalt Operations, and that study is expected to be ready by the end of March.
Disclosure: The author has a long position in Jervois Mining since its acquisition of M2 Cobalt.
