Recent reverse-circulation (RC) drilling at Kalgoorlie Gold Mining’s Providence prospect in Western Australia’s Goldfields region has turned up promising gold grades from just 20m depth, with broad runs of lower, but supportive grades prompting thoughts of open-pit mining.
Management says the similarity of mineralisation to its adjacent Kirgella Gift prospect – and a possible plunge intersection between the two plots – may provide thicker or higher-grade zones.
The first and best of the campaign’s top three holes yielded 4m at 1.99 grams per tonne gold from 24m, including 2m at 3.08g/t from 25m. It also bored through a deeper run of 6m at 2.11g/t gold from 80m, which includes 3m at 3.16g/t from 83m, followed by 4m at 1.37g/t from 91m including 1m at 4.8g/t from 94m. It capped the lot off with 2m at 2.58g/t gold from 101m, which includes 1m at 4.09g/t from 102m.
KalGold says the grade run from 80m to 103m (23m at 1.08g/t gold) was the trigger for its open-pit mining considerations.
The second of the top three holes nailed 2m at 1.71g/t gold from 20m, including 1m at 2.67g/t from 21m. The third hole ran for 10m at 1.12g/t gold from 143m, including 2m at 3.42 g/t from 145m.
Kalgoorlie Gold Mining managing director Matt Painter said: “Gold mineralisation at Providence is very similar to Kirgella Gift immediately north and occurs from 20m below surface, directly under transported cover. We predict that if these mineralised trends intersect, there could be significant hydrothermal fracturing and associated gold mineralisation.
Painter said the shallow gold mineralisation defined at Kirgella Gift and Providence would be incorporated into the company’s JORC (2012) mineral resource estimate and could also provide feed to a planned mill just 20km south of the project.
Management says results from Providence and its Kirgella Gift prospect, just 2.5km to the north, reflect similar mineralisation styles and believes the former is showing a distinct northerly plunge towards the latter. Intercept continuity between adjacent drillholes on the same sections and between sections can be confidently linked and define three separate gold mineralised structures, which dip steeply to the west within a north-striking and steeply west-dipping shear zone in ultramafic schist.
The ultramafic rocks are likely to have sheared preferentially to the enclosing, more brittle mafics and opened a plumbing system for gold mineralisation to exploit.
Encouragingly, the projected down-plunge intersection of mineralisation of the two prospects lies about midway between them at about 180m depth. Like many major structural intersections, it has the potential to carry thicker zones with higher or even bonanza mineralisation.
Management says it is assessing the most effective means of testing Providence and Kirgella Gift, which are the first two targets to be drilled at its Pinjin project, situated about 150km north-east of Kalgoorlie. It says additional RC and air-core (AC) drill programs are being planned for the priority area.
The Macquarie dictionary describes the word providence, in one meaning, as “provident or prudent management of resources”. And that could prove a very good omen for KalGold.
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