Whilst it mulls over some positive nickel-copper assays from recent shallow metallurgical test holes at its Stricklands prospect, St George Mining has two sets of drill rods spinning simultaneously at its flagship high-grade Mt Alexander project in WA’s north-eastern Goldfields. Both rigs are vectoring in on strong downhole EM, or “DHEM”, conductors which are amongst the deepest tested along the western extension of the Cathedrals Belt prospect.
One diamond drill hole is currently sitting just 25m above its interpreted target at 340m downhole. That target lit up like a Christmas tree in the original EM survey at 33,100 Siemens, setting the company up for a touch of excitement as the rotary truth diviner drill on towards the target.
The second drill rig is spinning 24hrs a day as it zeroes in on one of St George’s deepest EM plates which is expected below 505m downhole. The diamond hole reached 118.1m yesterday and still has a few hundred metres to plough through on its way to an even stronger 55,550 Siemens EM plate anomaly.
Whilst the company is currently focussed on its deep, high-impact drilling, it has also crunched the numbers on some metallurgical holes cut into much shallower massive sulphides at its Stricklands prospect along the western extension of the Cathedrals Trend.
The company’s technical team waved the x-ray fluorescence ‘wand’, or “XRF” analyser over the rock samples recovered from three drill holes, with massive sulphides recorded in each drill hole spread between 40m and 73m down-hole.
One drill hole returned preliminary, average XRF values of 3.84 per cent nickel and 0.61 per cent copper between 67.3m and 69m downhole and 3.0 per cent nickel and 1.6 per cent copper from 70.4m to 73.1m down-hole.
A second drill hole recorded average XRF values of 6.86 per cent nickel and 0.61 per cent copper from 40.2m to 41.7m and a second zone of mineralisation grading 4.92 per cent nickel and 5.4 per cent copper from 48.2m to 48.9m down-hole.
The third hole analysed by XRF returned 2.6 per cent nickel and 0.9 per cent copper from 47.2m to 50.6m downhole with definitive assay results for all drill holes eagerly awaited by St George’s management.
St George said around 300kg of drill core samples were now making their way to Canada for extensive metallurgical test work and process flowsheet design.
The company’s geologists were also pouring over the drill core from a couple of drill holes to compare the host rocks at each drill site. Petrographic analysis of rock samples from high-grade nickel sulphides at 111m downhole in one drill hole compare favourably with similar rocks seen in another hole, according to St George, down to 550m depth.
The company’s field team has started joining the dots to suggest the intrusive host rocks of the Cathedrals Belt start near the surface and plunge to the north-northwest. Furthermore, the trend covers more than 5.5km of strike length and remains open both at depth and laterally, which St George says provides a large target for future exploration drilling.
St George Mining Executive Chairman, John Prineas said: “We are very pleased with the latest petrographic analysis, which has again identified intrusive rocks that are not typically seen in the Yilgarn but are known to host significant nickel sulphide deposits in other parts of Western Australia.”
St George said the CSIRO has knocked on its door and is keen to run its eye over Mt Alexander’s unique, intrusive-style nickel-copper sulphide mineralisation. CSIRO’s world-leading expertise in developing ore genesis models for nickel mineralisation will be put to the test to understand the formation and emplacement of ore bodies such as St George’s Cathedrals Trend.
Elsewhere in St George’s nickel-rich exploration portfolio, the company is keen to get its hands on the impending assay results of a soil geochemical survey it ran across another tenement it hopes will reveal a Cathedrals Belt analogue for future exploration drilling.
Mr Prineas said:“Field work is in full swing at Mt Alexander with two diamond core rigs drilling, a soil survey in progress and preparations underway for aeromagnetic and moving loop ground EM surveys.”
“In the meantime, we are excited to be drilling two powerful EM conductors that are interpreted to have a massive sulphide source. We look forward to reporting results shortly.”
With nickel and copper prices threatening to find new highs, St George is moving as quickly as it can now to define the extents of its considerable mineralisation so it can start planning how it will come out of the ground as soon as possible in order for St George to take advantage of the newfound love investors have for base metals.
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By Matt Birney
