Recently-completed geophysical work at the Quorn prospect within Duke Exploration’s (ASX: DEX) high-priority Bundarra copper project in central Queensland suggests it could be up to five times larger than the nearby Mt Flora target.
A 3D induced polarisation survey in December identified conductivity anomalies at Quorn similar to those associated with copper-silver-gold mineralisation at the Mt Flora prospect.
Three large-scale and well-defined consistent anomalies were interpreted to be due to extensive sulphide mineralisation like Mt Flora.
The anomalies have the same conductivity as Mt Flora mineralisation and can be mapped to a vertical depth of 320m.
This equates to a volume of around 107.8 million cubic metres at Quorn compared to a volume of just 19.1 million cubic metres at Mt Flora.
Duke said the Quorn volume represents approximately 116 million tonnes of potentially mineralised rock, using the average measured density of the massive sulphide and disseminated mineralisation and a ratio of conductive rock to mineralisation at Mt Flora.
“This is more than five times larger than the tonnage of mineralisation defined by our drilling to date at Mt Flora and represents a significant new resource development target,” the company stated.
Large mineralised system
Duke chairman Toko Kapea said exploration at Quorn confirmed suspicions about the prospect’s size.
“We suspected mineralisation in the Quorn area might be bigger and more extensive than at Mt Flora and the IP survey confirmed that for us,” he said.
“We are now dealing with a potential system which could be more than five times larger than at Mt Flora.”
The new information will help with the planning of a second resource drilling program at Quorn, due to run alongside drilling at Mt Flora.
Mr Kapea said exploration also continues to confirm Bundarra’s prospectivity.
“Our geophysical surveys are providing compelling results which confirm we are exploring a very large mineral system at Bundarra where new discoveries will continue to be made into the future,” Mr Kapea said.
“We are growing in confidence that new discoveries will continue to be made at a rapid pace into the future.”
In addition to the Quorn 3D survey, a gradient array IP survey was recently completed at the nearby Isens underground mine area.
The results suggest historic copper-silver-gold mineralisation could extend to the south-west into hornfels metamorphic rock and be much larger than initially interpreted.