North-west Queensland is well-known for the high-quality minerals and metals hiding just below the surface, but for one Mount Isa man the real treasure is not found through mining, but through metal detecting.
Dave Knox purchased his first metal detector in 2007 after waiting years for a high-quality relic detector to enter the market.
His main aim was to collect coins, a hobby that started in early childhood after finding wartime pennies at the family station on the New South Wales-Victoria border.
“I found my first coin when I was four years old, with my dad in the garden,” he said.
“I guess you could say it’s a very passionate hobby.”
The surface miner and father-of-five has since upgraded to a superior model, which he takes out nearly every day.
“It’s a small or shallow gold detector, but I use it for everything — coins, relics, jewellery,” Mr Knox said.
“Anything that’s made of metal. If it’s there, it finds everything.”
Going on a treasure hunt
Using the detector to scan the ground, hovering and moving side to side, the machine beeps constantly.
Ground balance sets the detector for the type of dirt Mr Knox is on.
Frequencies show what kind of metals are present.
“It sends a pulse down that detects what’s there, gives me an idea. It’s a quartz liquid readout digital screen,” he said.
Mr Knox has tuned his settings with different sensitivities for various targets, to better sort the wheat from the chaff.
“At the moment I’ve got it to where I can say ‘Nup, rubbish’, and keep walking,” he said.
“In coins I’m pretty much spot on. I know what I’m digging before I dig it.”
Mr Knox goes treasure hunting every chance he gets, uncovering everything from old Australian pennies to metal plaques from machinery, and even dog tags so ancient they have just two digits in the phone number.
“Regardless of how long I do it there’s always that moment of … ‘What is it … what is it?'” he said.
“It’s either disappointment, or it’s like … wow!”
Spare change funds favourite hobby
While pocketing any vintage coin, Mr Knox also collects currency to fund his hobby further.
“Because it was a fairly large monetary outlay for my family, I’ve made it pay for itself, maybe four or five times in the seven years I’ve had it,” he said.
His biggest tally for one day was $197 in coins.
Meanwhile, long-lost trinkets are given a new lease of life.
“They all basically go on one big chain that’s escalated into something quite heavy, and probably quite expensive with all the precious metal on it,” Mr Knox said.
Those lonely charms and lost earrings, each with a past life, have made a unique charm bracelet for his young daughter.
“There’s hearts, there’s small crosses, there’s a little owl with jewels on it … there’s even a koala, which is silver,” he said.
Treasure chest or trash heap?
Mr Knox said the extent of rubbish he uncovered was astounding.
“Ring pulls and bottle caps and beer bottle caps, there are just hundreds of thousands of them,” he said.
“I can blank some of them out through the functions of the machine, but they’re always there.”
As well as recovering relics for people in a panic, Mr Knox has been reunited with his own lost items.
“Everybody loses stuff, I lose stuff,” Mr Knox said.
“But if I do lose stuff, I know where to go back and find it.”
‘Don’t dig a pit’
Most of the treasure lies in the top layers of earth and does not need much elbow grease to unearth.
Using a pin-pointer to finely target his prize, Mr Knox digs tiny holes, minimising any damage.
“If you’re out somewhere and you dig a big hole, you’re in trouble. You don’t do that.”
He said most places required people to ask permission before they could go digging, and he has permission for several secret spots in town.
“If you’re over there fossicking through someone’s lawn or something it’s not very much appreciated,” he said.
“I don’t do damage. And you either get a yes or a no, it’s that simple.”
But after years of practice, Mr Knox warns his precision method of treasure hunting is not for everyone.
“Ninety-five people out of a hundred would give up after the first three or four times they went out, through sheer frustration,” he said.
“It’s just not something that’s easy.”