Argonaut Resources NL (ASX:ARE) is planning follow-up drilling at the Nyungu copper-cobalt deposit in Zambia to increase cobalt and copper tonnages.
Drilling by Argonaut has already defined an exploration target of between 12,000 and 24,000 tonnes of contained cobalt at a grade of 0.08% to 0.12% cobalt.
READ: Argonaut Resources has market's attention with Olympic Dam style target
Peak cobalt result from diamond drilling (in 2011 and 2012) is 81.5 metres at 0.12% cobalt from 183 metres, including 23 metres at 0.21% cobalt.
Shallow drilling to focus on cobalt oxide zone
A program of shallow drilling has the potential to significantly upgrade copper and copper-cobalt mineralisation in the oxide and transitional zones.
This is particularly significant because of the favourable metallurgical properties of cobalt oxide. Much of the cobalt produced in the DRC is mined from cobalt oxide deposits.
Argonaut plans to target these zones for drilling that will provide both resource estimation data and metallurgical sample for dense media separation and leach test work.
Samples to be sent to Australia for testing
Contained copper and cobalt at Nyungu is within three weathering zones: oxidised, transitional (mixed oxide and sulphide), and fresh (sulphide).
Each of these zones presents demonstrated metallurgical opportunities for production.
Metallurgical samples have been selected from existing drill core and these samples are being exported to Australia for test work.
Initial test work will involve a mineralogical study of the four mineralisation types. Results of this initial work will direct further test work and infill drilling at Nyungu Central.
Aiming to upgrade cobalt tonnages and grades
Of the 48 drill holes completed at Nyungu targeting copper, 10 intersected significant cobalt mineralisation.
Since cobalt was not specifically targeted during previous campaigns, scope remains for a meaningful upgrade of cobalt tonnages and grades.
Cobalt oxide tonnages are particularly interesting due to potential low-cost, short lead-time processing options.
Zambia: mineral endowment, favourable metallurgy and lower political risk
The LME (London Metal Exchange) cobalt price is about US$88,000 a tonne, or around 175% higher compared to January 2017.
Recent battery-related demand for cobalt has exposed the fragile nature of cobalt supply.
Over 70% of the world’s cobalt is coming from the DRC, a risky mining jurisdiction.
Zambia is a far safer and lower-risk jurisdiction that benefits from political stability, robust mining law and functioning courts.