It is tempting fate to describe conditions in the small end of the mining sector as nearing boom-time confidence but a 40% increase in delegate numbers at an annual Explorers Conference is a good starting point for a spot of mood measuring.

Last year’s roll up of 1000 fee-paying delegates at the RIU Explorers Conference in the WA port city of Fremantle has been eclipsed by this year’s 1400 – with “walk-ins” expected to take the total closer to 1500 for a 50% increase year-on-year.

“They’ll be hanging from the rafters,” was the snappy description of the high-quality problem confronting conference organiser, Stewart McDonald, as he manoeuvres his way through a crowded entry at Rydges Hotel and thinks aloud about how to handle the numbers in what is quite a small facility.

“Something triggered the surge in numbers about four weeks ago. Until then we were tracking 2018 numbers, then bookings went nuts.”

If a seasoned campaigner like McDonald doesn’t know what’s caused an explosion of interest in his Explorers Conference then that’s probably because he’s been too busy to notice what’s happening on commodity markets where records are tumbling after seven lean years.

Apart from cobalt, which crashed a few months ago thanks to over-supply from reopened African mines, there is barely a mineral or metal not moving up. Or at least not falling which is almost as good these days as most miners and explorers have their costs under control.

Gold, the Australian explorer’s favourite for the last 150 years, is the biggest single drawcard at the Fremantle conference which runs for two-and-a-half days. Yesterday was the half, with a 1.30pm kick-off and 5.45pm close with poolside drinks.

At more than A$1850 an ounce, gold is sitting comfortably at an all-time high, with A$2000/oz the next target.

Today and tomorrow will be full days with a single topic dominating presentations and sideline chatter; exploration.

Unlike some other mining conferences, the Fremantle event is not a trade fair, it really is an event where explorers meet other explorers and investors.

Not that speakers at the conference will shy away from a spot of spruiking, leaving investors to sort the wheat from the chaff.

But as an early warning, now might be a good time to sit up and take notice of what’s said in Fremantle over the next two days because the hints of something significant happening have rarely been clearer.

Iron ore, a mineral consigned a few weeks ago to the file marked “yesterday’s leader”, has returned with a rush just when no-one was looking.

The sharp price rise to around $US88 a tonne might not see the year out as supply rushes to fill a gap created by outages in Brazil, but it is possible that Brazil’s problem-plagued mines could be out for longer than expected.

That’s why forgotten stocks such as Grange and Brockman this week hit 12-month share price highs, along with the big boys of iron ore, Fortescue, Rio Tinto and BHP.

Analysed from any direction and the seeds of a sustainable recovery in mining have been sown, largely because that most fundamental of economic measures, supply and demand, is out of kilter with demand reasonable while supply stumbles after years of under-investment in exploration and project development.