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The days of stumbling across ore sticking out of the ground are over.
Once upon a time, discovery meant dust, hammers, and luck. You could follow a gossan, trace a creek, or trip over an outcrop that shimmered under the sun. But that era’s done. The surface has been picked. Today, the real discoveries lie under cover in the ground we can’t see and most explorers still don’t truly understand.
We’re no longer chasing what’s visible. We’re chasing what’s invisible and the uncomfortable truth is we’re drilling more, spending more, and finding less. There are plenty of reasons for it, some deposits will never become mines for geological, environmental, or economic reasons. Others are being held back by the constraints of today’s capital markets.
According to Geoscience Australia’s 2024 review, mineral exploration expenditure fell around 7% year-on-year. Roughly 6 million metres were drilled nationwide, depending on the dataset, yet only 45 maiden resources were announced. That’s around 130,000m drilled for every new discovery and most of those never reach production.
Globally, S&P Global reports that the share of grassroots exploration collapsed to a record low of ~22%. Majors are playing it safe; juniors are broke. Across the board, exploration budgets are being redirected toward brownfields expansions rather than new frontiers.
‘Quarterly thinking’ killing real discovery
We’ve let quarterly thinking replace generational vision, the industry is obsessed with “adding ounces”, not finding systems. Most of those ounces stay in the ground and get recycled through each cycle, drilled again and again for “resource growth”. The old-school exploration model poking around where others already are is easy to justify on paper, but terrible for discovery rates which lead to production.
The results are a pipeline that is thinning. MinEx Consulting data shows discovery costs have risen two to threefold since the 1990s. It now takes roughly US$140-200 million ($213-304 million) to find an average gold deposit, and often it’s worth about half that.
The fundamental issue is that the easy rocks – the ones sticking out of the ground – have already been found. About 80% of Australia’s basement geology is concealed by soil, sand, or sediment. Once you’re under 20-30m of cover, traditional exploration tools like surface mapping, geochemical sampling and visual cues simply stop working. You’re effectively blind.
That’s one of the reasons why discovery rates have cratered. We’ve been using 20th-century tools on 21st century terrain.
But here’s the positive, those covered areas are where the biggest upside lies. Geoscience Australia’s mapping shows vast belts of buried, fertile geology stretching across the continent that are the same age, same chemistry and same structural settings as known mineral camps. We just haven’t looked properly. We’ve been staring at the wallpaper instead of what’s behind it.
If there’s one thing modern geoscience has taught us, it’s that “cover” isn’t an obstacle, it’s a filter. That thin layer of regolith hides mineral systems but doesn’t erase their fingerprints. The trick is learning to read those signals. And right now, a quiet revolution is underway in how we see through that mask.
Deep geophysics reshaping exploration
Deep geophysics like gravity, magnetotellurics, and airborne electromagnetics (EM) is giving us 3D x-rays of the crust. Machine learning is stitching it all together, turning messy datasets into probability maps. Programs like AusAEM (Australia’s national AEM program) and AusLAMP (national magnetotellurics grid) are rewriting the country’s geological base map, while AI-driven tools are correlating geophysics and geochemistry to predict what’s under the dirt.
The work around Nova is a prime example; high-resolution EM imaging in the Fraser Range consistently maps nickel sulphides beneath ~30m of sand terrain once written off as too hard. The result was a commercial discovery in ground that others walked straight past.
In the Pilbara and Gawler, new isotopic geochemistry is doing the same. We can now trace subtle metal ions and isotopic halos that migrate through cover almost like a geological scent trail. We’ve entered an age where discovery depends as much on data scientists as it does on drillers.
You can see the shift in the statistics. Australia drilled more than 6 million metres in 2024 but recorded fewer than 50 new deposits. Globally, grassroots exploration hit record lows. The few regions bucking the trend include parts of Latin America’s copper belts where teams are embracing deep, undercover targeting.
Even MinEx CRC, which exists to de-risk these plays, puts it bluntly: most of Australia’s mineral potential lies beneath cover, but our knowledge stops at the surface. Their National Drilling Initiative is literally punching holes into the unknown, providing pre-competitive data that private explorers can build on. It’s one of the few programs treating exploration as a national science challenge rather than a corporate lottery.
And still, it’s not enough. We’ve mapped the stars more accurately than the basement beneath the Simpson Desert. That’s how much opportunity remains untapped.
Olympic Dam proves the point. When BHP’s (ASX:BHP) predecessor drilled the first hole in 1975, the ground was flat, covered in sand, and geologically uninspiring. The team followed gravity and magnetic anomalies, pushed through ~325m of barren rock, and kept going. Hole RD10 hit ~170 metres at 2.1-2.2% copper, plus gold and uranium. That discovery reshaped Australia’s economy. It also proved that the future of exploration lies not in luck, but in persistence, theory, and funding discipline.
Nova-Bollinger: Conviction and science deliver success
Fast forward 40 years to Nova-Bollinger, discovered by Sirius Resources in 2012. Buried beneath 30 metres of sand, it wasn’t obvious. It was geoscience-led EM surveys, magnetic models, and sheer conviction. The pattern is the same: breakthroughs come from teams who believe in the model and back it with capital. They ignore the noise, trust the data, and stay in the game long enough to be right sometimes down to the last few holes, as I’ve seen Mark Bennett speak about in the past.
Truth is, we’ve built an industry where even the best geologists can’t get funding unless they’re chasing a headline. That’s backwards, the next tier-one discoveries won’t come from glossy decks. Sure, you might raise some capital that way but that ends, the real discoveries will come from those drilling into the quiet, covered corners of the map. The marketing comes after the discovery.
The data, the history, and common sense all say the same thing: the next generation of mines will be found under cover.
The easy discoveries are gone. The exposed belts are mature. What’s left is harder, deeper, and riskier but far richer in potential. Governments are finally catching up. The UNCOVER initiative, launched by the Australian Academy of Science, calls for systematic, science-led exploration. It’s a blueprint for how to explore under cover. We need policy to match that vision: stronger tax incentives for exploration, more government-funded pre-competitive data, and commitments from majors to dedicate a fixed share of budgets to genuine greenfields science.
Because if we don’t invest in looking under cover, someone else will and they’ll own the next generation of metal supply.
Exploration has always been an act of optimism, looking at an empty plain and believing something extraordinary lies beneath. That hasn’t changed. What’s changed is how deep we have to look. The easy rocks are gone. The next frontier is invisible. And the companies that learn to see through the dirt literally and figuratively will define the next century of mining.
The map hasn’t run out of ore. We’ve just stopped looking deep enough.
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