Metal Hawk Limited (ASX: MHK) has confirmed thick, high-MgO ultramafic rocks also extend south of the Commodore discovery as part of its regional nickel sulphide exploration at the Berehaven Project, 20km south-east of Kalgoorlie in the West Australian goldfields.
The Commodore nickel sulphide discovery in September 2021 confirmed the potential for a significant mineralised komatiite system at Berehaven, with the company’s maiden reverse circulation (RC) drilling programme intersecting 5.9% Ni.
Whilst Metal Hawk has been exploring the nickel and gold mineralised system at Commodore with reverse circulation (RC) and diamond drilling, regional nickel exploration has also continued with aircore (AC) and RC drilling and extensive ground geophysical moving loop electromagnetic (MLEM) surveys across the broader Berehaven Project area.
In conjunction with our first gold-targeted diamond drilling program at Commodore, our latest RC drilling at Berehaven has really focused on exploring the fertile ultramafic stratigraphy along strike from the Commodore nickel sulphide discovery,” Managing Director Will Belbin said.
“We are very excited by the width of ultramafic rocks and the signature of strong nickel-copper-PGE anomalism in the latest batch of results and look forward to drill-testing the fresh rock below and more of these exciting regional prospects which historically have been very sparsely explored for nickel. It’s also very pleasing that we’ve been able to identify new untested EM targets in favourable geological locations.”
Recent RC drilling has intersected a zone of strong Ni-Cu-PGE geochemistry at the new Torana prospect, located 1.5km northwest and along strike from Commodore. BVNC017 returned a zone of 10m @ 0.20% Ni, 424ppm Cu and 126ppb PGE from only 25m depth, at the top and interpreted western margin of an extremely weathered ultramafic unit.
Drilling beneath this zone intersected a thick (>60m) interval of weathered ultramafic rocks, with highly anomalous Ni-Cu-PGE geochemistry (also at the western margin of the unit).
BVNC026 returned 35m @ 0.26% Ni, 132ppm Cu and 45ppb PGE from 120m, which included 10m @ 0.32% Ni, 240ppm Cu, 87ppb PGE from 120m. BVNC030 was drilled 60m further north on section 6,585,760mN and intersected the same anomalous Ni-Cu-PGE zone in highly weathered ferruginous saprolite, returning 40m @ 0.42% Ni, 234ppm Cu and 104ppb PGE from 100m, including 12m @ 0.51% Ni, 605ppm Cu and 236ppb PGE from 101m.
These significant geochemical results indicate a likely magmatic nickel sulphide source. Geological logging and geochemistry suggest that the ultramafic sequence at Torana is overturned, therefore the target basal contact position is situated at the western margin of the ultramafic unit.
Follow-up RC drilling in progress is designed to test the bedrock for nickel sulphide mineralisation beneath the extremely weathered zone of Ni-Cu-PGE anomalism, with a downhole target depth of 200m. RC drillholes will be cased with PVC and a campaign of downhole electromagnetic (DHEM) surveys will be carried out in order to test for any conductive responses related to massive nickel sulphide mineralisation.
Commodore
Metal Hawk has also significantly progressed exploration along the southern extension of the Commodore ultramafic sequence. The company’s geologists are encouraged by the continuation of the Commodore ultramafic stratigraphy, with several RC holes intersecting significant thicknesses of high-MgO ultramafic rocks at downhole depths greater than 100m. The majority of assays from these holes are pending and expected within the next four weeks.