Geological smoke leads PLC Resources to bigger WA gold target

PLC Resources has kicked off follow-up reverse-circulation (RC) drilling at its Rochefort gold prospect, part of the company’s Abbotts North gold project in Western Australia’s Murchison region, chasing what it believes could be a larger gold system lurking beyond its maiden drill pattern.

An eight-hole, 2400m campaign will target northwestern and down-dip extensions of the prospect, where earlier drilling revealed strengthening gold values and a suite of geological and geochemical clues, suggesting the first holes may have clipped the edge of a bigger mineralised system.

The earlier five-hole, 1020m reconnaissance campaign, reported in July and representing the first modern gold drilling at the grassroots Rochefort, returned anomalous gold up to 0.4 grams per tonne (g/t) in three of five holes. The gold was hosted within highly fractionated dolerite alongside alteration, sulphidation and pathfinder geochemistry that PLC says warranted a closer look.

The hotspot had already left a trail before drilling, with a 400m by 350m gold-in-soil anomaly and quartz-hematite vein rock chips grading up to 11.7g/t gold.

‘We’ve built a strong technical case for a larger gold system beyond our maiden drilling that all point to the northwest and at depth.’

PLC Resources executive director Simon Phillips

Subsequent analysis gave PLC more indicators to follow. The company says gold values increase northwest and with depth alongside increasingly evolved dolerite, while sodic alteration interpreted as albitisation, magnesium depletion and weak but persistent sulphides, predominantly pyrrhotite, strengthen in the same direction.

Multi-element work has added another pointer, withsulphur levels rising alongside elevated gold whilearsenic and antimony become relatively depleted. PLC believes the association indicates increasing proximity to a mineralising fluid pathway rather than a distal dispersion halo.

The host rocks add another dash of geological spice. PLC says fractionated dolerites can make prime hunting ground for orogenic gold, pointing to Kalgoorlie’s famed Golden Mile dolerite as a geological cousin where evolved rocks often channel gold-bearing fluids before helping squeeze out their precious cargo.

PLC Resources executive director Simon Phillips said: “It’s great to have the rig turning again at Rochefort. We’ve built a strong technical case for a larger gold system beyond our maiden drilling that all point the same way, to the northwest and at depth. This program is designed to directly test that target.”

Management expects PLC to complete the campaign in 14 days and will provide updates as drilling progresses. First assays are anticipated in four to six weeks, with results to follow as they are received and validated. The program is covered by existing environmental and heritage approvals and will be funded from existing cash reserves.

In parallel, the company will continue advancing a newly interpreted regional structural corridor across its roughly 400-square-kilometre Abbotts North project. Geophysics identified a previously unmapped fold extending for more than 14km along the eastern margin of the greenstone belt that had not been recognised on existing government geological maps.

The fold’s hinge intersects a deep-seated crustal structure – geological plumbing PLC regards as a first-order gold targeting feature. The company says such features can provide long-lived pathways for mineralising fluids, while their intersections can create favourable sites for those fluids to focus and deposit gold.

The historic Abbotts goldfield has a strong pedigree, with records showing production of 41,000 ounces at a head grade of roughly 31g/t, principally from shallow quartz reefs. Large parts of the district have since seen little systematic modern exploration.

Rochefort also sits 21km north of New Murchison Gold’s Garden Gully project in the same Abbotts Greenstone Belt. Garden Gully contains a 4.42-million-tonne resource at 2.5g/t gold for 359,300 ounces and hosts its producing Crown Prince gold mine.

PLC’s maiden drilling may not have delivered headline grades, but management believes it handed the company something potentially more useful – a geological treasure map. The next batch of holes will find out whether those clues lead to the main event.

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