Perth-based explorer Dreadnought Resources (ASX: DRE) has made a high-grade massive sulphide, supergene and oxide discovery at the Orion target within the Tarraji-Yampi nickel-copper-gold project in Western Australia’s West Kimberley region.
Assay results from the first six mineralised follow-up holes drilled at the prospect have confirmed a mix of copper (up to 7.4%), silver (192 grams per tonne), gold (34.2g/t) and cobalt (1.66%), with the mineralisation commencing from 1m under cover and extending to at least 240m along strike and 150m down dip.
Significant intercepts were 16m at 2.2% copper, 38.7g/t silver, 6.6g/t gold and 0.4% cobalt from 77m including 2m at less than 0.1% copper, 4.8g/t silver, 27.6g/t gold and 1.5% cobalt from 77m, and 7m at 4.7% copper, 83.3g/t silver, 4.9g/t gold and 0.2% cobalt from 82m.
Also returned was 19m at 1% copper, 23.2g/t silver, 1.1g/t gold and 0.06% cobalt from 92m including 2m at 2% copper, 56.8g/t silver, 5.6g/t gold and 0.25% cobalt from 92m, and 3m at 3.5% copper, 92.9g/t silver, 1.9g/t gold, 0.14% cobalt and 4.2% zinc from 107m.
Geophysical modelling indicated the mineralised body could extend to at least 500m depth.
Further positive results
Dreadnought managing director Dean Tuck expected the thick, high-grade intercepts to be followed by further positive results once the remaining assays were received next month.
“This is an amazing outcome from what is only our second drill program at Tarraji-Yampi and the first lot of exploration since [historic work in] 1958 and 1972,” he said.
“It is an indication of the potential for this highly-prospective and underexplored ground to produce more discoveries.”
Orion consists of multiple magnetic and electromagnetic anomalies within a thick, 4km long Ruins Dolerite and sediment package.
A number of the anomalies sit adjacent to significant cross-cutting structures which could potentially provide fluid pathways for Proterozoic copper-silver-gold-cobalt mineralisation.
The prospect’s massive sulphide mineralisation consists of pyrrhotite-pyrite-chalcopyrite-cobaltite and zones into more pyrrhotite-pyrite-chalcopyrite-sphalerite and galena-rich compositions to the north and occasionally along the margins of the massive sulphide intervals.
Dreadnought said the zonation was likely due to a temperature gradient or multiple overprinted pulses within the mineral system.
Oxide and supergene mineralisation is developed in the weathered portions of the lodes down to 20m depth and is marked by iron-rich gossans and secondary copper carbonates in the oxide portions and chalcocite in the supergene.
A palaeochannel of up to 5m thickness covers the shallowest portions of the mineralisation, making it blind at surface.
Mr Tuck said three holes for 357m were drilled into the magnetic anomalies with multiple zones of copper and cobalt minerals intersected within sheared, sulphide-altered mafic rocks.
The results indicated that additional lodes of massive sulphide mineralisation may exist within the broader Orion area.