First-pass air core (AC) drilling by Kalgoorlie Gold Mining (KalGold) on a blind target at its Kirgella West prospect, 140km northeast of Kalgoorlie, has been rewarded with good hits up to 3.66grams per tonne (g/t) gold over a 1200m strike.
The 63-hole, 3518m program is adjacent to the company’s Kirgella Gift and Providence gold deposits, with their combined 76,400-ounce gold inferred resource, and produced strong gold anomalism and potentially economic gold grades over a wide area.
The three prospects are part of KalGold’s Pinjin gold project which straddles a section of the prospective, regional-scale Laverton Tectonic Zone.
The best result among the top three holes includes an 8m intercept assaying 2.29g/t gold from 60m, including 4m going 3.66g/t gold from 64m, and a second hole produced a 4m intercept running 1.05g/t gold from 52m.
A third hole bored through 8m grading 0.59g/t gold from 48m, including 4m at 1.02g/t gold from 48m.
KalGold says 16 of the 63 holes drilled - or 25 per cent - returned significant anomalism when it applied its in-house approach to defining and prioritising anomalous zones and trends from multiple intercepts within a drill pattern.
The outcome is remarkable for a maiden scout program over a conceptual geophysical and structural target area, particularly one completely devoid of outcrop.
The Kirgella West tenement sits beyond but on the margins of the regional-scale Lake Rebecca palaeo-drainage system. Transported cover at the prospect can attain as much as 50m depth, although it thins eastward to about 3m at Kirgella and Providence.
Gold anomalism and some good hits have been obtained over a 1200m strike broadly mirroring the regional structural trends as interpreted from geophysics. The anomalism and hits extend up to about 350m wide across strike.
Kalgoorlie Gold Mining managing director Matt Painter said: “The first-pass Kirgella West air core drill program has discovered extensive anomalism and gold mineralisation immediately west of the Kirgella Gift and Providence gold deposits, where KalGold has previously defined a shallow JORC Code (2012) Inferred Mineral Resource of 2.34 Mt at 1.0 g/t gold for 76,400 ounces of gold.”
KalGold believes the initial drilling has picked up irregular and probably structurally- controlled gold mineralisation that is also reflected in bottom-of-hole pathfinder geochemistry, including arsenic, copper, zinc, potassium and rare earth elements.
Elevated bottom-of-hole gold values are also present on the northernmost drill line over an east-west distance of 320m and remain open to the north.
The 8m at 2.29g/t gold intercept is associated with altered and sheared ultramafic rocks that appear similar to those at Kirgella Gift.
That gold hit coincides with a north/north-west striking structure that is part of the Laverton Tectonic Zone, an important crustal suture that is key to much of the regional mineral prospectivity, including Ramelius Resources’ 1.4-million-ounce Rebecca-Roe gold project, about 25km south of Kirgella West.
The 8m intercept grading 0.59g/t gold from 48m nailed gold in veined and altered mafic-ultramafic rocks. Geophysics suggests that east/north-east structures which cross-cut the Laverton Tectonic Zone trend could control the distribution of gold mineralisation in that area.
Across its reconnaissance drilling, KalGold has been remarkably successful in tweezing out some important secrets from an area that has remained poorly-understood, mainly due to extensive surface cover.
The broad gold anomalism and scattered better hits could be the first indications of primary gold potential hiding under cover at Kirgella West and - aided by geophysics - provide important insights into some of the likely structural controls.
With gold anomalism being most pronounced in the northern part of the drilling grid, KalGold considers it may be necessary to define the full footprint of anomalism with further AC drilling across that area
Eventually, some reverse circulation drilling will also be required to better penetrate the deeper zones and potentially intersect primary gold mineralisation once particular gold trends and associations have been better defined.
Results are still awaited for an extra five AC holes tacked onto the east end of the second line at the northern extremity of the grid in November, which may serve to broaden the anomalism eastwards in this area.
Results from those holes are slated to be available early in the new year.
Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au
By Doug Bright
