ASX-listed Classic Minerals has unexpectedly uncovered what appears to be gold-bearing river gravels at its Kat Gap project in Western Australia.
According to the company, a quick onsite crush and pan yielded minor amounts of visible gold in the dish.
Classic says the removal of the over-burden in its trial mining operation was progressing as anticipated and the trial pit had reached 5 metres below the surface before ancient river gravels started to appear on the pit floor. Surprisingly, previous reverse circulation drilling had not identified the rock layer.
Management believes the river gravel or conglomerate layer is the remnants of an ancient river, near the base of the overburden, that at one stage passed over the ore body thousands of years ago.
A conglomerate is a geological descriptor for a sedimentary rock with large, rounded clasts consolidated by finer sand and clay size particles. Often conglomerate mineralisation has been transported by water historically.
Conglomerates are known to be prospective for hosting gold. Notably, the success of the Canadian company, Novo Resources’ Beatons creek conglomerate gold project has drawn a slew of explorers to scour the Pilbara region for similar riches.
Classic says the lateral dimensions of the conglomerate layer are yet to be constrained, however, it estimates the thickness to be between 1m and 2m.
The river gravels are going to be kept separately for detailed sampling and assaying.
With the mining crew running on time and on budget Classic estimates the bulk sample mining program will run for about another six weeks.
The company says the next major milestone for the bulk sample will be when Kat Gap’s “ore body” is exposed for the first time.
The junior explorer holds total mineral resources of 8.24 million tonnes grading 1.52 grams per tonne gold for 403,906 ounces of gold contained.
Interestingly, the bulk sample mining was intended to assist in calibrating mining parameters ahead of production. Now the company believes the discovery of the river gravels could add valuable ounces to the bulk sample and future open-pit mining operations.
With the prospective rock layer effectively falling in its lap, there is no doubt Classic will be itching to learn more about its curious, and possibly lucrative, find.
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