The company’s latest aircore drilling campaign has extended known anomalism to more than 2.5 kilometres and this includes grades of up to 1.1% copper, 0.7% nickel and 0.04% cobalt.
Great Boulder has the option to earn a further 24% for a total of 75% by spending an additional $250,000 over four years.
Shares were up almost 6% to an intra-day high of 7.6 cents.
Winchester is 40 kilometres north of Great Boulder’s Yamarna project, which comprises the Mt Venn and the Eastern Mafic deposits.
Great Boulder Resources exploration projects in the Yamarna region.
Based on metallurgical tests from Mt Venn, the high nickel-tenor at Winchester makes it attractive as a blend for Great Boulder’s Yamarna project along with its potential to host higher grade nickel mineralisation.
The Winchester aircore campaign comprised a total of 118 holes for 3,776 metres drilled on a wide-spaced grid with the aim of verifying and improving interpreted stratigraphy.
Downhole assay results have identified a significant zone of coincident nickel, copper and PGE anomalism over a strike extent of almost 3 kilometres.
Maximum nickel values define a plus-1500ppm anomaly coincident with plus-100ppm copper and plus-10ppb PGE anomalism.
This geochemical anomaly extends from the Winchester prospect in the north to the southern tenement boundary.
Concurrently, the company has completed a high-resolution ground gravity survey at the JV to assist with geological interpretation.
Winchester JV and Great Boulder 100% tenement boundaries overlain on RTP aeromagnetic data.
Previous drilling at Winchester identified significant nickel-copper-cobalt-PGE mineralisation, including 19 metres at 0.6% copper, 0.3% nickel and 0.02% cobalt from 106 metres and 13 metres at 0.9% copper, 0.3% nickel and 0.02% cobalt from 138 metres.
Great Boulder has started planning for a follow-up drill program.
New tenement granted
A new exploration tenement located south along strike from the Winchester prospect and owned 100% by Great Boulder has been granted for an initial five-year term.
The recently delineated geochemical anomaly is open to the south and trends onto this newly granted tenement.
Great Boulder plans to extend future work plans onto the new tenements once all regulatory approvals are in place.