Greg Bruce goes hunting for treasure with one of NZ's top metal detectorists

Leading metal detectorist Gary Coker: seeking buried treasure. Photo / Alan Gibson

Greg Bruce goes metal detecting and gets more than he bargained for

In the early evening of a foolishly hot day in late January, I parked at the edge of Lake Rotorua, 14km from the town of the same name, next to a blue Mitsubishi Triton ute belonging to Gary Coker, one of New Zealand's leading metal detectorists. The ute contained: that detectorist; his 9-year-old daughter; their dog; a high-end, waterproof, Minelab metal detector; a purpose-built tool for digging in underwater environments; and a homemade floating sieve made from a supermarket bread tray, a roll of gutter guard and child's pool floaty.

"You used my floaty!" his daughter said.
"I did use your floaty," he said.
"You're sad!" she said.
"Well, you never use it," he said
"Yes I do!" she said.

I had searched long and hard - and with considerable pained awareness of the inherent irony - to find a metal detectorist willing to take me treasure hunting. Although Coker had granted me access in November to the 1700-member, private Facebook group Metal Detectors NZ Aotearoa (MDNZA), which he runs with friend Andrew Staveley, I had failed to convince a single one of its many members from in and around Auckland to let me accompany them on a hunt.

In fact, my request, in early December, had yielded only a few "jokes", a couple of names of people who turned out not to be interested, two direct messages asking me to include in this article some boring detecting minutiae; and a strangely aggressive comment, which read, in part: "Enough already. Nobody else will speak up then I will even if I get removed from the group for it. We don't need any more promotion of metal detecting in Auckland …"

This comment generated several more likes than my original post and attracted more supportive replies too. One read: "No need to worry bro ... not very many people now days [sic] buy let alone read news papers [sic] or for that matter watch tv ... its [sic] all online now, paper [sic] media is becoming a thing of the past just like the phone book and junk mail .. .destined for recycle [sic] or landfill."

Even one of the leading retailers of metal detecting equipment refused to help, even after I told them what great publicity it would be, which was something they should already have known. They wrote: "Me and everyone I know is part of the club on Facebook. If your [sic] not having luck there, your [sic] not going to have any luck."

The only person willing and able to take me out was Coker himself, "The Godfather", as I have never heard anyone call him. But Coker and I lived a long way apart, our schedules didn't match, blah blah: opportunities were scarce. There was a lot of boring back-and-forth before we were able to meet on that warm, clear January day at Lake Rotorua. No matter, though, because five seconds after Coker dipped his detector in the water, we hit silver.

The thrill of the find is what had brought Coker to detecting, me to Coker, and metal detectorists across the globe to a hobby that is among the world's nerdiest. It's so exciting to know that at any moment you might unearth something astonishing that you can easily forget you're wearing headphones and belt-bag and waving a giant wizard wand.

A scoop full of hope and possibly treasure. Photo / Alan Gibson

"Astonishing" is a relative term, obviously. Pretty much every year in the UK, someone digs up a massive horde, the rough equivalent of a Lotto jackpot. Last year, a group of detectorists found $10 million worth of 1000-year-old coins on a farm in Somerset. In the Australian deserts and in the United States, detectorists are digging for - and occasionally finding - massive gold nuggets worth hundreds of thousands of dollars. In New Zealand, one veteran detectorist posted on the MDNZA Facebook page about cashing in nearly two years' worth of detecting finds for $735.10.

"I would say 95 per cent of the people on our Facebook page," Coker said, "are interested in this stuff simply for its historic value. Very few people are motivated by the money. It's always nice to make a bit of money but none of us really ever go out with the idea of making money."

Motivation can come in many forms, but the bulk of the ground-based treasure in New Zealand comes in the form of rings and coins. If you're into coins, you're a coin shooter. You can find silvers, sovs, young vickys, old vickys, thrups and spendies. If you find a sov you're in the sov club. If you find a whole bunch of coins at once, it's called a coin spill.

Coker likes a good coin - his shed at home is full of them - but today he had his heart set on rings: "I would hope - you can't get too cocky - but I would hope in a place like this that's a regular swimming site, that there would be a ring," he said.

High-quality detecting, of the sort practised by Coker, is not just a case of turning up and swinging the coil ("Just going out for a swing" / "Anyone got time for a quick swing?") His ability to find stuff, well-documented in text and pictures on the MDNZA Facebook page, is the product of experience, technical expertise, high-quality equipment and, most importantly, copious research. He had chosen this spot because he'd deduced that the presence of the general store across the road, directly across the lake from Rotorua, meant this had probably once been a high-traffic boat route. His assumption and hope was that people would once have landed their boats here, dropping assorted metal valuables in the process, including, hopefully, their rings.

From this broad theory, he further refined his search: "You can actually see if you look along where I'm walking ... you've got the sand coming down and there's a definitive line where it changes direction, so you've got the flat lake bottom, here where my foot is; and then it sort of goes up on a shelf to the sandy beach - not very pronounced - where the constant wave action is cycling and anything heavy's getting pushed in and pushed down. So this is a line where the targets would be. So this is the first place you want to check."

Okay dude, sure thing, whatever. Less talky; more findy.

We were in deliciously warm, knee-high water, and Coker had just finished telling me how much trash we were likely to find, when the Minelab started squeaking and booping.

"I've actually got a nice signal here," he said. "That says 21."

He started fiddling with the detector. The noise intensified. "What I've done right now," he said, "is used my pinpoint feature. It's now dialled the target in … So now what I do is quickly take away my machine, I put my scoop there, I dig into the ground and have a scoop … pull that out of the way and then check."

He put the detector back over the hole he'd just dug. It was silent.

"See?" he said. "The tone's gone. It's now in the scoop."

He lifted the scoop - it was full of sand and mud and associated lake-bed materials - and tipped it into the floating bread crate, which was attached to him by belt and harness. He shook the crate around a bit. Suddenly, there it was! Treasure! It was a bit black around the edges but mostly still quite shiny. It had a picture of George VI ("King Emperor") on one side and a Māori figure, crouching and holding a taiaha, on the other.

Gary Coker, bathed in the golden light of a successful hunt. Photo / Alan Gibson

"1937!" I read. You could hear from the pitch of my voice I was excited.

He said: "That tells me that that's a New Zealand silver shilling, because they were silver from 33 to 47."

It was fascinating and unsettling to think this coin had been in that mud for, how long? Seventy years? Eighty? More? Imagine lying in the dirt for that long, assuming you would never be found, then suddenly you were. How many people, some of them possibly famous, had walked or swum over the top of you in that time, with no idea of your existence?

"You don't seem that impressed about that," I said to Coker. "Is this fairly common?"

"That, for most people, would be a fantastic find," he said, "but I find them all the time. If you wanted to keep that as a souvenir, you're most welcome to."

Of course I wanted to. As I've already expressed, I was excited.

Coker's daughter, swimming nearby, yelled, "Find some gold!"

Five minutes after the discovery of that first coin, the thrill still fresh upon me, Coker's Minelab again started showing a good number and again he scooped a load of wet sand and mud into the bread crate.

He shook it. The goop spread out. "Ooh, look at that!" he said.

There on the surface was another - clearly very old - coin. I couldn't believe it! He picked it up and wiped its face with his thumb. It was almost completely black, but you could just make out the face on the back. It was King Edward VII, who came three monarchs before the guy Colin Firth played in The King's Speech. The date on the coin was 1908.

"That's a nice one!" Coker said.

Again it was impossible to say how much of the coin's life had been spent in that lake but, it seemed safe to say, most of it. What must it have seen in its long existence, and what might it have seen, had it not spent so long in the lake?

We'd only just waded into the water and already we'd found two coins with a combined age of 195 years.

"Amazing!" I said. "We've been here five minutes."
"Yeah," he said, "Now you know how my metal detectorist mates feel!"
He handed me the coin. "Again, you can keep that if you want," he said.

In spite of his casual attitude, Coker was obviously excited. He admitted that the speed and success with which we had found these first two coins made him want to come back with a pair of waders and give the place "a good smashing".

But it was as if the lake felt his excitement and resented it, because it immediately clammed up. For the next 20 minutes, we swung that coil low and slow across the shallows of Lake Rotorua and we found nothing but rubbish: a rusty nail, a metal hook, a surprising amount of glass, a whole tomato.

Coker didn't mind this. From his belt hung a large pouch in which he stashed all the trash. "I call us metal detectorists earthworms," he said. "Earthworms that eat metal." He said he loves going home with a big pile of junk, knowing he's left the environment in a better condition than he found it.

We found three tyres; we found a chunk of can ("A big chunk of arse"), that had been melted down, probably in a campfire, then chucked in the lake. We found bits of can that had been shredded ("canslaw"), probably by tractor lawnmowers, then chucked in the lake; we found ring-pulls and bottle caps and the foil top from an old glass milk bottle; we found part of a tube of glue.

"I'm glad we're starting to find these, because this is what detecting's normally all about," he said. "That's the thing: people get a detector and they're like, 'I'm going to go find a treasure' and then you go out and spend hours and hours and hours just digging that s*** and it's horrible."

Man alone (with birds). Photo / Alan Gibson

It wasn't horrible though. It was a delightful evening and, as I say, the water was warm, Coker's dog ran around chasing sticks, while his daughter swam nearby. Finds or no finds, it was a provincial New Zealand idyll.

"I really like this sort of wandering along," Coker said.

Just as it started to feel like we'd found everything we were going to find, we found a nail. It was just a nail but it was also not just a nail; it was a square nail.

"People who find square nails would be, like, 'Wahoo!'" Coker said. By his estimate, the nail had been made in the early 1900s, and had probably been part of someone's boat back in the day. "What that tells me," he said, "it coincides with that 1908 penny really. It tells me there probably is a little bit of history here."

As if the lake wished to prove him right, suddenly it began to bestow that history upon us. Coker said, "We must be due a coin" and one minute later he scooped up a 1947 New Zealand penny. "You can see the tūī on there," he said. He let me keep it.

Four minutes later, he scooped a 1908 English penny - our second of the day. "What are the chances?" he said. "Look at the colour. It's been on the lakebed for forever!" He let me keep it.

Two minutes after that, he scooped what looked like a pepper shaker. It was one of the least exciting things I'd ever seen but the most excited I'd seen Coker all day. It was an art deco-style light switch or fitting, made of Bakelite, probably from the early part of the 20th century. "Guarantee I'm going to soak that when I get home and try to unscrew it," Coker said, "but it's old, man!"

"Like there's no value in that whatsoever," he said, "but that's cool." He emphasised "cool" in such a way that it was clear he meant it in the sense of "seriously awesome" rather than "chill" or even "quite good".

Two minutes later, he found part of an old harmonica. "You can actually see where the reeds would have been!" he said. "Junk, but cool junk. I like finding stuff like that."

A minute and a half later, we looked down into his sieve and spotted another old coin. "Now we're talking!" he said. "We might've cracked the 1800s!"

On the coin was the image of Queen Victoria. "What we call the veiled head," he said. The veiled head, he told me, was found on coins from the late 1800s until Victoria's death in 1903.

He turned the coin over and ran his finger over the date: "Oh!" he said. "Not quite! 1901."

He let me keep it.

In the shallows. Photo / Alan Gibson

To summarise: in 46 minutes, we had found three coins of more than a century old; two other coins from the first half of the 20th century; one square nail; one partial harmonica, one Bakelite light fitting and one piece of Caltex sign. I had nothing to compare it to, admittedly, but it seemed like a pretty productive three-quarters of an hour.

Coker told me it's not unusual for him to go detecting alone but he frequently goes detecting with a couple of friends, including an ex-colleague he refers to exclusively as "Bottom-feeder Scott."

Bottom-feeder Scott, Coker said, first became interested in detecting after hearing Coker talk about some of his finds at work: "And now I can't get rid of the bastard."

Two days before our outing, the pair had been out together when Coker found a silver ring. Bottom-feeder Scott came over to have a look, started detecting nearby, and almost immediately found a ring for himself.

"And I'm like, 'Bro, that is disgusting,'" Coker said. "'You bottom-feeding bugger.'"

This sort of presumably good-natured banter also appears fairly frequently between detectorists on the MDNZA page, although it is a place of mostly sweet, often touching, warmth and fellowship.

On July 6, for instance, Coker posted on the page: "Just a big thumbs-up to my fellow detectorists! For a tiny country with a tiny population with a short history it never ceases to amaze me what we find in the ground!" He attached a photo showing 10 arms in the air, all with thumbs up. Comments included: "Darn right Gary", "Bang on Gary" and "I love this Group, it gives such inspiration and encouragement, even when its [sic] just a nail that you find."

This is true. A large proportion of the page's content is people posting photos of their discoveries and other people saying nice things about them, no matter how lame those discoveries: "Sweet finds", "What a great hunt", "Luv that coin", "Awesome finds", "Fantastic finds", "Very nice", "Sweet haul mate", "Nice work", "Well done", "Sweet as finds", "Nice wee haul there bud", "great finds mate", "cool finds mate" and "That looks like a partial detonation. Digging up any UXO [unexploded ordnance] is very dangerous unless you can positively ID."

Of all the nice things you might find with a metal detector, could any be better than connection with other human beings? The answer to that is subjective, obviously, but I would argue in favour of $10 million worth of 1000-year-old coins.

We were knee-deep in the water when Coker fielded a phone call from his wife. She was making hamburgers for dinner and the time was fast approaching for him to go and eat them. It was clear he didn't really want to leave, though. "It can be reheated," he said.

We pushed on, along the narrow strip in the shallows where the constant wave action was cycling or whatever. Coker's machine started giving a warning sound, suggesting the presence of a big chunk of arse.

"That sounded bloody horrible," he said. "Probably rubbish, but you don't know until you dig it."

He dug it. He tipped the scoop into the floating sieve. He laughed. There, glinting among the blackness, was something that was obviously not a chunk of arse.

"You want to pluck that and tell me what it is?" he said. He sounded excited.

I plucked it.

"Oh!" he said.

"A ring!" I said.

"Wooo-hooooo!" he said. "Has it got a hallmark on it?"

I read from the inside of the ring: "925. Mexico, maybe?"

"Oh! Really? Even better!"

The 925 meant it was sterling silver. The "Mexico" meant it was made in Mexico, probably from melted coins, which he seemed to find interesting. It wasn't especially valuable - based on silver's current market value, he estimated it at about $3 - but he didn't care. It had an intricate pattern which I would describe, probably incorrectly, as Aztec, and it looked like it had come from a particularly tiny finger. It was quite beautiful.

He didn't let me keep it.