Legend Mining appears to be on the cusp of a new nickel-copper discovery at its Rockford project in WA’s rich Fraser Range base metals province. Diamond drilling has intersected nearly ten meters of nickel-copper rich sulphides at the Northerly prospect in a mafic-ultramafic intrusion that is akin to the known fertile intrusions that host the revered Nova-Bollinger and Silver Knight deposits.
The Perth-based explorer said regional exploration has been completed at the Rockford project over three tenements which contain the Crean, Northerly and Hurley prospects. According to Legend, the prospects have been identified as favourable nickel-copper-cobalt targets through systematic exploration utilising aircore drilling and ground-based moving loop electro magnetic – or “MLTEM” surveys.
A total of five diamond holes were drilled for 1,424.2 metres. Of the five holes, two were drilled into the Crean prospect, two were drilled into the Hurley prospect and one hole went into the Northerly prospect.
Interestingly, the Crean and Hurley prospects lie within the same western structural corridor that hosts IGO’s celebrated Nova-Bollinger discovery and the newly acquired Silver Knight nickel-copper-cobalt deposits, some 110 kilometres and 150km to the southwest respectively. Nova-Bollinger boasts resources totalling 11.8 million tonnes at 1.76 percent nickel, 0.71 percent copper and 0.06 percent cobalt. This equates to about 208,000 tonnes of contained nickel, 84,000 tonnes of contained copper and 7,000 tonnes of contained cobalt.
Legend’s diamond drilling was designed to follow up on anomalous air core drilling and modelled MLTEM conductors that can sometimes point to the presence of massive sulphides that are prospective for base metals.
Previous pathfinder aircore drilling threw up intercepts of 11m going 0.42 per cent nickel, 0.01 per cent copper and 0.03 per cent cobalt along with a wider 34m hit at 0.19 per cent nickel and 0.03 per cent cobalt.
Whilst samples from the core are at the lab awaiting assay, the company said highly prospective mafic and ultramafic lithologies have been identified at all three prospects.
Encouragingly, at the Northerly prospect, Legend reported that fresh magmatic sulphide blebs of pyrrhotite, pentlandite and chalcopyrite were noted over nearly ten metres suggesting the potential discovery of a new fertile mafic-ultramafic intrusion at the Rockford project according to the company.
Legend Managing Director Mark Wilson said: “The early success from the Northerly prospect is particularly pleasing with anomalous geochemistry indications from aircore, sulphides in intrusive host rocks observed in diamond drill core and a large shallow conductor from the MLTEM survey.”
“The significance of all these programmes will be better understood once all assays and analysis of the results are collated.”
In addition to the diamond drilling at the Northerly prospect, Legend also reported it has completed a MLTEM over the greater prospect area and a highly prospective conductive feature has been identified west of the diamond drill hole. Management said it is planning additional MLTEM surveys now to further define the feature prior to initial aircore testing.
Regionally, Legend is actively exploring the extents of its broader tenure, completing an additional 213 aircore drill holes for 12,168 metres over a selection of high priority targets. Assay results are pending and aircore drilling is ongoing.
The Rockford project area comprises 3088 square kilometres in the prospective Fraser Range terrain south-east of Kalgoorlie-Boulder. Legend made a significant find there in 2019 with a mineralised intrusion at Mawson on the eastern side of the project area. With the likes of Nova-Bollinger and Silver Knight nickel-copper deposits inhabiting the same structural corridor, Legend appears to be tantalisingly close to making its own major discovery in this most lucrative of terranes.
Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au
By Matt Birney
