Drilling at Northern Cobalt’s (ASX: N27) Woollogorang project in the Northern Territory has identified a significant induced polarisation (IP) chargeability anomaly at the flagship Gregjo copper prospect.
The anomaly is believed to lie directly below previously-identified copper mineralisation, extending up to 200 metres out from the Gregjo fault.
At least five of the holes drilled along the fault intersected mineralisation containing over 1% copper along a distance of more than 300m.
Best results were 7m at 1.23% copper from 1m, including 1m at 4.24% copper; 15m at 0.53% copper from 5m, including 4m at 1.08% copper; and 20m at 0.72% copper from 1m, including 1m at 1.4% copper and 3m at 1.67% copper.
Also recorded were intervals of 11m at 0.65% copper from 16m, including 1m at 1.97% copper; and 3m at 1.57% copper from 13m and 1m at 0.78% copper.
Managing director Michael Schwarz said the drilling results add weight to Gregjo’s potential.
“The identification of significant copper mineralisation above an extensive IP chargeability target at Gregjo has opened up the potential for a significant new copper mineralised system, only 3.4km to the south of our Stanton cobalt deposit,” he said.
“These results continue to show the extent of mineralisation which runs through Wollogorang.”
Mr Schwarz said the Gregjo system is much larger than Stanton and has the potential to be many times the size of the cobalt deposit at surface.
The Gregjo prospect was originally identified by CRA in the 1990s as a surface geochemical anomaly with minor copper mineralisation, and limited extent.
Re-interpretation and subsequent drill testing by Northern Cobalt in 2018 identified the source of the mineralisation causing the surface geochemical anomaly and a follow-up IP survey was conducted to define possible depth extensions.
The results of the survey identified the large chargeable feature beneath the currently identified mineralisation, which the company has interpreted to represent “an extension of high-grade oxide copper mineralisation identified at surface to primary mineralisation at depth”.
A drilling program is now being planned to test the IP anomaly at Gregjo in conjunction with promising copper targets generated in October at nearby Running Creek prospect.
At midday, shares in Northern Cobalt were 4% lower at $0.072.