Wiluna Mining Corporation's first foray into drill-testing the down-plunge extensions of high-grade gold mineralisation at the historically significant East Lode has come up trumps, returning an impressive 9.4 metres at 4.87 grams per tonne gold that included 1.8m delivering 9.74g/t.
The East and West Lodes were the largest producing areas mined at Wiluna, with the East Lode coughing up 720,000 ounces at 6.7g/t between 1931 and 1946. The parallel-running West Lode handed over an additional 690,000 oz grading 8.6g/t between 1932 and 1946. Both lodes were mined to depths of about 600m.
Impressively, the duo still has plenty in the tank. Wiluna said when combined with the current mineral resource, the East and West Lodes have a large pre-production endowment of approximately 3.5 million ounces at grades of 5.4g/t of the precious yellow metal.
Surprisingly, very little exploration exists below the current workings, with a smattering of wide-spaced holes drilled below the lodes in the 1990s that hinted at the continuity of the gold structures at depth.
The company’s maiden drill hole into East Lode has confirmed the continuity of high-grade gold mineralisation about 200m down-plunge of the limit of historical mining and the current mineral resource envelope.
Success with the drill bit follows a rehash of the geological and ore forming models.
The company says high-grade shoots at East Lode are predicted to occur at the junction of steeply east-dipping structures with rock unit boundaries. Additional subtle north-plunging and south-plunging high-grade shoots are also aligned with pre-mineralisation structural trends.
The revised geological model provides the company with the tools to better target new discoveries.
Wiluna Mining Corporation's Executive Chair, Milan Jerkovic, said: “This outstanding intercept confirms our strategy to discover new high-grade sulphide shoots as we test multiple targets across the Wiluna Mining Centre, particularly in the South Mine Area but right across our very large gold system at Wiluna, as we look to expand beyond the current mining activity in the North Mine Area.”
Management says the first hole has also punctured the West Lode with sulphides visible in the diamond core, along with shearing and alteration indicative of low-tenor gold mineralisation. Assays are still pending.
Importantly, the West Lode intersection is reportedly 700m below the limit of historical drilling and the current mineral resource, hinting at the large-scale continuity of the West Lode structure.
A total of eight holes have been designed to target extensions of the East and West Lodes along 1000m of strike and 700m of down-plunge extent on the East and West Lode structures.
Wiluna is seeking to amass multiple new high-grade shoot discoveries with an ambitious 40,000m discovery drilling campaign currently underway, with the rods spinning at East and West Lode, Bulletin North and Squib.
Drilling has been designed to systematically test nine large-scale targets for additional high-grade gold shoots “under the headframe”. Management says the intention is to substantially enhance the early years of the current mining plan by increasing the underground ore grade to ramp up gold production.
The company’s strike rate is on point with the latest East Lode intercept, following on from a first-hole probe of its Bulletin North Discovery target that yielded a staggering 3270 g/t gold from 634m and a 1.5m hit going 8.30 g/t gold from 570m, with the latter housed in a broader 10m section running 2.80 g/t gold from 563m.
The Wiluna mining centre has been worked through an astounding 125-years and currently hosts a gold endowment of about 10 million ounces.
Wiluna looks to be charging ahead in its quest to unfasten the latch on the treasure trove of riches that could lurk in the depths of the historically significant gold field.
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