Where there’s Smoke: Elephant hunt heats up in Macquarie Arc

• NSW’s Macquarie Arc is home to the Cadia mine, one of the jewels in Newmont’s global portfolio
• Newmont’s chief geoscientist says there’s more porphyry deposits to be discovered in the district
• Juniors including Waratah, Legacy and Kincora are hoping improved access to funding will lead to discoveries

While Western Australia claims the crown when it comes to domestic gold production, some of Australia’s biggest gold mines lie in New South Wales.

Chief among them, the Cadia gold-copper mine near Orange is one of the jewels in Newmont Corporation’s global portfolio and one of the key attractions behind its 2023 takeover of previous owner Newcrest Mining.

Newmont Corporation (ASX:NEM) chief geoscientist Dr Anthony Harris told IMARC in Sydney this week that Newcrest and Newmont had benefitted from 25 years of operating Cadia.

“What I mean by that is that actually we were able to acquire, in British Columbia, on the strength of understanding the Macquarie Arc porphyries, similar lookalike porphyries at Red Chris and then subsequently the epithermals around Brucejack in British Columbia,” he said during a panel discussion.

What excited Harris was that comparing the two districts, a lot more porphyries had been discovered in BC.

“What I’m intrigued by is the fact that actually Cadia alone represents 55 million ounces of gold endowment. It has a thermal footprint, and it’s probably seven kilometres along the Earth’s crust. There’s significant metal endowment. There has to be more,” he said.

More recent discoveries in the Macquarie Arc include Alkane Resources (ASX:ALK) Boda-Kaiser discovery, with a resource of 8.3Moz of gold and 1.5 million tonnes of copper, and more recently, Waratah Minerals’ Spur discovery.

“There’s a lot of places in the Macquarie Arc where there’s been a lot of smoke for many years, but we’re seeing genuine fires there now,” NSW chief geoscientist and head of the NSW Geological Survey Dr Phillip Blevan said.

Spur excites

Harris said the recent Spur discovery, which is just 12km from the Cadia mill, exemplified the opportunity in the Macquarie Arc.

Waratah Minerals (ASX:WTM) shares ignited in August when the company reported an intersection of 208.7m at 1.17 grams per tonne gold from 514m, including 89m at 1.96g/t gold, including 38m at 3.61g/t gold at Spur.

The discovery came about from reinterpreting the Cargo Intrusive Complex and targeting the margins of the main early-stage intrusive complex for wallrock-style epithermal-porphyry mineralisation.

“I’ve liked the Cargo Complex for a long time,” Waratah managing director Peter Duerden said.

“You could see that the focus there, historically, hadn’t been in the priority search space.

“If you look at all the East Lachlan systems, the margins of these big, magnetic, intrusive complexes is where you want to be. All the big deposits are located there, so that search space at Cargo at surface hadn’t been explored thoroughly enough, we thought, so hence why we’re there.”

Duerden and his team have been exploring in the Macquarie Arc for many years with different companies.

“You fail a lot of times as an explorer. You fail a lot, and if you keep doing that with different companies, you end up understanding what the key controls are,” he said.

“The fact of the matter is at Cargo, as a junior explorer, we like the opportunity just to drill shallow gold. We saw an opportunity to build a story around that good technical approach, which stems back, the team and myself, exploring the Macquarie Arc with different companies for the last 18 years.”

New concepts

Legacy Minerals Holdings (ASX:LGM) managing director Chris Byrne told the panel it was the company’s strategy to explore in overlooked regions of NSW.

“One of the things that we really saw in the Macquarie Arc is that there has been a huge focus on chasing the big porphyries, and that sort of left a bit of a void, which represented an opportunity that we saw for some of these more unknown areas, maybe not as well liked geologically,” he said.

One of those projects is the Bauloora gold-silver project, which the company believes represents one of the largest, preserved epithermal vein systems in NSW with very limited drill testing.

“It is relatively early stage in its concepts, so there’s a lot of work to get done on it,” Byrne said.

“There’s a lot of smoke and the footprint is quite significant. I think the latest round of geochemistry and sampling … we have done down there, even over the last couple of months, has doubled the size of the known veinfield footprint.”

Like Waratah and Legacy, Kincora Copper (ASX:KCC) has been looking for new exploration concepts in existing data for its Trundle project in the region.

“Trundle, we really like because we have some new concepts, similar to what Pete’s brought to Cargo, and at Trundle, we’ve found the biggest mineralised skarn in New South Wales and made a couple of other discoveries,” CEO Sam Spring said.

“The challenge for a junior explorer is, how do you keep funding it? We put a million dollars into Trundle in 2023 and got some pretty good results, but it didn’t move the needle for our share price.”

Funds flowing

Both Kincora and Legacy have adopted a project generator model, whereby they bring in larger partners to fund exploration.

Since changing its funding model, Kincora has inked two earn-ins with AngloGold Ashanti, one with Earth AI and another with Fleet Space Technologies in the Macquarie Arc alone, as well as another with Orbminco in Mongolia.

“Today, we’ve done five asset level deals that have unlocked potentially $100 million of partner funding,” Spring said.

“We’ve seen $6.5 million go into the ground in the first nine months of that strategy, so we’re very keen to come back and do Trundle justice, but it’s just trying to find the right funding mechanism to do it, because they’re great prizes, but they take time and they take money.”

Similarly, Legacy has done joint ventures with companies including S2 Resources and Earth AI.

It had Newmont as a partner at Bauloora, until earlier this month when the major withdrew.

However, it attracted Rio Tinto as a partner this month on its Thompson project, unlocking up to $25 million of further funding.

Off the back of its Spur results, Waratah raised $30 million in August to accelerate exploration. It has three rigs on the ground now and another two on the way.

Spring said Waratah’s discovery had been positive for all the explorers in the district, but there was the potential for a further re-rating.

Again using the comparison of the Golden Triangle in BC, Spring said explorers there had risen by 1.7 times this year to a cumulative market capitalisation of over $2 billion.

“In our part of the Macquarie Arc, we’ve re-rated 2.5 times, but it’s only half a billion cumulative market cap,” he said.

“In terms of a global perspective, we’re doing well in New South Wales, we’re catching up, but we’re still behind other comparable jurisdictions.”

At Stockhead, we tell it like it is. While Legacy Minerals Holdings and Waratah Minerals are Stockhead advertisers, they did not sponsor this article.