Legend Mining’s mission to conquer Western Australia’s mighty – but patience-testing – Fraser Range has taken a positive new twist, with geophysical data defining three conductors possibly related to nickel and copper.
The conductors, identified during a maiden high-power fixed loop electromagnetics (HPFLTEM) survey over the company’s entire “Octagonal” intrusive complex in the past three months, have positive drill intercepts with visual sulphide mineralisation identified in core.
The company says the conductors are interpreted to relate to extensions of that mineralisation and management plans to finalise its subsurface model upon receipt and integration of the final geophysical data from an extended survey, which is planned for March-April next year. The modelling is expected to generate new drill targets for next year’s field season.
Legend Mining executive chairman Mark Wilson said: “We are cautiously optimistic with the results of this survey to date. The evidence of nickel-copper mineralisation in drillholes proximal to the modelled conductors and the strong conductive source to the east of the Octagonal Intrusive Complex are both positive takeaways.”
The company says conductor one is about 400m by 400m in size, dipping at 60 to 75 degrees towards the north/north-west and buried under about 400m of cover. It is located down-dip along the Octagonal intrusion contact proximal to mineralisation intersected in diamond-core drillholes, OCT0184 and OCT0190.
Management says conductor two is bigger, about 1km by 1km, dipping at 65 to 75 degrees towards the south-east and buried under about 300m of cover. It has been interpreted as a zone relating to blebby through semi-massive nickel-copper sulphide mineralisation visually estimated in core from diamond drillhole OCT0005, which intersected the conductor’s top edge.
The company’s visual estimates from OCT005, which was drilled to 1662m, are 1 to 5 per cent disseminated and blebby sulphides from 630.9m to 635.8m, 20 to 40 per cent matrix sulphides from 635.8m to 637.1m and 40 to 80 per cent semi-massive sulphides from 662.95m to 663.1m.
Legend says conductor three is about 1km by 1km and buried under about 250m of cover, dipping steeply to the north-west at about 80 to 90 degrees. It is interpreted as the southern extension of a zone of remobilised semi-massive nickel-copper sulphide intersected in diamond drillhole OCDD003, which was drilled to 909.4m.
It says the hole hit a zone between 500.62m to 501m depth in which 40 and 80 per cent semi-massive sulphides were visually identified. The hole also hit a 1m thick lense of non-textured sulphide mineralisation visually estimated at between 20 and 40 per cent from 501m.
Management says a fourth conductor was also interested from the HPFLTEM data. It is modelled as a deep, low-conductivity feature correlatively on seismic data and interpreted to be the feeder structure at the base of the Octagonal intrusive complex.
The company says it is encouraged by the correlation seen between two diamond drill holes and a strongly-conductive source extending to the east of the completed survey area. One of the holes, OCT0189, has visual mineralisation estimated at greater than 80 per cent massive sulphides from 282.68m to 282.75m.
Both holes hit nickel-copper sulphide mineralisation within fertile ultramafic sills proximal to the strong conductive source, confirming the extension of mineralisation outside of the main Octagonal intrusion body.
Legend says that mineralisation style is identical to that seen within the renowned Nova-Bollinger setting, which holds 11.8 million tonnes averaging 1.76 per cent nickel, 0.71 per cent copper and 0.06 per cent cobalt.
The Octagonal prospect lies within Legend’s 3000-square-kilometre Rockford project in the Fraser Range, about 250km east of Kalgoorlie. The company says future work at Octagonal will include more diamond drilling, downhole electromagnetic surveys and petrophysics and the assaying of selected core intervals.
Octagonal is just one of a group of seven high-priority prospects identified by Legend across the Rockford project. They include magmatic nickel-copper sulphide-style targets at Mawson, Octagonal, Magnus, Hurley and Crean and volcanogenic massive sulphide-style zinc-copper-silver targets at Shackleton and Worsley.
Copper prices have seen a slight recovery since October and sit today at about $12.50 per kilogram. The reddish metal is the third-most widely used metal in the world and is listed as a critical material for energy transition technologies by the majority of countries.
The Octagonal prospect has been named after one of Australia’s greatest-ever thoroughbred racehorses of the same name. And Legend is cracking the whip in a bid to start galloping after prized mineralisation through some of WA’s toughest terrain.
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By Andrew Duffy
