A strategic review by rare earths-focused Critica and Premier1 Lithium at their Yalgoo joint venture (JV) project in Western Australia’s Murchison region has prompted a shift from lithium exploration to gold and copper.

While Critica has maintained a strong focus on its emerging Jupiter rare earths deposit, also in WA’s Mid West, the change in thinking at Yalgoo has also today captured the market’s attention. The news prompted a small spike in Critica’s share price, while Premier1’s stock jumped 80 per cent during intraday trading this morning on the biggest volumes since it listed in early 2022.

Although the JV’s initial exploration efforts were focused on lithium at Yalgoo, it has since identified extensive gold and copper prospects and has now kicked open the door to exploring for the two commodities in an area renowned for big discoveries of the respective metals.

The Yalgoo project spans 220 square kilometres in the northern Yalgoo-Singleton Greenstone Belt, a region known for major discoveries such as 29Metals’ Golden Grove and Red5’s Deflector mines.

Historical exploration of the Wadgingarra area in the northern part of JV ground was conducted mainly by Mount Kersey Mining from 1985 to 1989 and revealed gold mineralisation in subvertical quartz veins. An estimate from that work reported 390,000 tonnes at 3.7 grams per tonne gold down to a depth of 40m and extending into neighbouring ground held by Spartan Resources.

Key targets included Crescent, Olive Queen and Cumberland. At the time, the area was tested with a 73-hole drilling program and additional potential was identified at three other additional targets. Notably, exploration data from the 1900s has also revealed untested gold mineralisation in multiple zones within the Yalgoo tenement, offering additional immediate opportunities.

The unearthed historic drill results highlighted high-grade gold intercepts, including one of 5m at 5.1g/t from 1m, another of 10m at 6.4 g/t from 8m and 2m running at 20.8g/t from 10m. Further historic surface rock chip sampling thrown up from desktop studies revealed multiple high-grade assays including 9.4g/t and 7.4g/t gold, in addition to 6.6 per cent copper.

A more recent electromagnetic (EM) survey in 2020 by Critica discovered four high-priority volcanogenic massive sulphide (VMS) ore drill targets, 10km north and along strike from the Golden Grove zinc-copper-gold mine that contains 750,000 tonnes of copper, 1 million ounces of gold and 3 million tonnes of zinc.

The promising finds, which have been overlooked since the 1990s, have now presented the JV with multiple high-potential drill targets. Moving forward, the JV plans to initiate a fieldwork program to test and confirm the targets, with an eye to establishing a broader mineral portfolio than just the lithium prospects.