How Scotland forged a rare alliance between amateur treasure hunters and archaeologists

ON JUNE 21, 2020, Mariusz Stepien headed to a farmer’s field to see what he could find. The pasture he picked that particular Sunday—the first time he’d been out in months, after Scotland imposed movement restrictions in the early phase of the COVID crisis—looked like a tourism ad. The small rise sits in the middle of a lush green field a few miles from the town of Peebles, once a center of the nation’s wool industry and now a bedroom community for nearby Edinburgh.

The River Tweed meanders through the valley below, and on a cloudless day the lush, rolling peaks of the Scottish Borders mark the horizon in all directions. A waist-high stone wall runs along the field’s edge, penning in some 200 sheep, and a narrow two-lane road runs along one side.

Stepien, a carpenter by trade, owns a small home remodeling business. But his passion is metal detecting. For the past nine years, regardless of the weather, he’s spent every Sunday he could walking fields and pastures in the countryside, searching for buried treasure. Sometimes he goes alone, sometimes with like-minded friends. “I wait the whole week for Sunday,” he says. “For me, it’s the nicest way to spend time in a beautiful landscape.”

To find buried metal, Stepien sometimes paces for 12 hours straight, sweeping the wand of a four-foot-long metal detector (a Minelab Equinox 800, to be exact, a popular model at the higher end of the market) back and forth. Based on technology developed during World War II to help find and defuse land mines, the devices use an electromagnetic coil to generate a current that, when it hits a conductive material, sparks a signal—a whine he hears in his worn black headphones.

Over the years, he’s learned to tell from the pitch what sort of treasure is hidden below the surface, and how much. A low tone might mean an iron nail. Slightly higher could be a silver coin, or the brass end of a hunter’s spent shotgun shell. The louder the noise, the bigger the find.

As he mounted a small rise in the middle of the meadow that summer day, his headphones filled with a clear, high tone—the strongest he had ever heard. Kneeling in the thick grass, he lifted a rock the size of a loaf of bread, then began clearing loose soil underneath with a small paintbrush. After a few minutes he plucked something green, round, and hard out of the dirt.

At the other end of the field, Stepien’s friend and fellow detectorist Dariusz Gucwa was making his own way through the grass when his walkie-talkie crackled to life. “Dariusz, please come now,” Stepien called. “I think I found something big.”

In the following weeks, this find would spur a massive excavation effort begun out of a unique Scottish office called Treasure Trove, a two-person team that fields reports of artifacts discovered in local soil. In practical terms, the agency is a go-between: On one side are hobbyists, keen-eyed gardeners, beachcombers, and anyone else who uncovers an artifact from the past. On the other are museums.

By law, amateur treasure hunters like Stepien are required to report anything with potential historical or archaeological importance, from stone tools to silver coins, along with information on where it was found. The scheme is rooted in the ancient dogma that any unclaimed property found in Scotland belongs to the government. Or, in the tradition-laden language of Great Britain, the Crown.

Over the past 20 years, Treasure Trove has emerged in Europe as an example of collaboration between heritage authorities and the metal detecting community—two groups historically very much at odds. Responsible recreational searching, advocates argue, helps find objects and sites archaeologists don’t have the budget or time to search for.

Finding common ground

The relationship between archaeologists and metal detectorists like Stepien is usually fraught. In Scotland and neighboring England and Wales, there’s an active community of hardcore hobbyists who share their finds in online chat rooms and meet for occasional metal detecting “rallies” that bring dozens of people together in farm fields to search, share stories, and show off their finds.

While the hobbyists like to think of themselves as treasure hunters or amateur archaeologists, many professionals prefer the term “looters.” Experts say metal detector finds often wind up damaged, disappear into dusty attics, or get sold on the black market for stolen antiquities. In countries like Italy, Greece, and Spain, where people have used metal detectors to locate and plunder intact graves or archaeological sites, police have special units devoted to tracking down illegal excavators.

Even well-meaning amateurs can do harm. Over-eager hobbyists sometimes dunk coins in vinegar to clean off their protective patinas or straighten bent pieces of metal, potentially erasing clues as to how they were once used or why they were discarded. Once they are removed from the find spot and that damage is done, the object’s “context,” in archaeological terms, is lost forever.

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There’s a philosophical element, too. In many countries, ancient artifacts and ruins are considered public heritage. “To us, archaeological items don’t belong to the owner of the land, but to the state, to everyone,” says Ignacio Rodriguez Temino, a curator at the Department of Heritage in Seville, Spain, who researches heritage laws. “We think no one has the right to become the owner of what they find if it is an archaeological object.” In Spain and most other European countries, using metal detectors to look for artifacts is against the law.

Until the 1990s, metal detecting occupied a sort of gray area in the UK, allowed on private land but frowned on by authorities and archaeologists. Instead of cracking down on hobbyists, in 1996 Scottish authorities decided to take an “if you can’t beat them, join them” approach. Though the legal principles behind it have been around for centuries, creating an official Treasure Trove office and a transparent compensation system with publicly listed fees gave metal detectorists and others an incentive to report finds that might otherwise be lost.

“Metal detecting is happening, and it’s very hard to enforce a ban. As archaeologists, we might as well engage with these people. You get a lot more information if you gain their trust.”

—Pieterjan Deckers, Free University of Brussels

England, Wales, and Northern Ireland initiated a similar effort, called the Portable Antiquities Scheme, in 1997. Over the last five years, a handful of other European countries—including Finland, the Netherlands, and Denmark—have moved in the same direction. “It’s a pragmatic stance. Metal detecting is happening, and it’s very hard to enforce a ban,” says Pieterjan Deckers, an archaeologist at the Free University of Brussels who researches metal detecting and helped set up a reporting system in Belgium. “As archaeologists, we might as well engage with these people. You get a lot more information if you gain their trust.”

Ideally, metal detecting can be a way to enlist members of the public in data-gathering. Individual coins, for example, might not have much value on their own, especially when they’re plucked from farm fields torn up by decades of intensive plowing. But with a database of coins discovered by detectorists, a canny researcher might be able to understand the political reach of a past kingdom, or map out the places people were most likely to settle at different periods. Metal detecting has revealed new insights about the Viking colonization of England, for example, by allowing researchers to map coins and metal finds.

The Portable Antiquities Scheme has registered more than 1.5 million finds in a database since it began. “British archaeology has been revolutionized by the understanding of metalwork,” Deckers says. “If metal detecting happens within a certain set of rules, it can help preserve the past.”

When a lead comes into Treasure Trove—usually a few each day, typically cellphone snaps sent via email—agency head Emily Freeman and her colleagues reach out to archaeologists, museum curators, and other experts, sharing photos and adding finds to a national database. If they decide an object belongs in one of the country’s museums, the artifact is claimed on behalf of the government by the impressively named Queen and Lord Treasurer’s Remembrancer. In most years, Scottish museums have intervened in around 150 cases this way, with each case representing anything from a single coin to a hoard of hundreds of artifacts.

Finders, meanwhile, are given a reward based on the market value. In 2017, that ranged from less than $15 for a musket ball to $2.5 million for a hoard of Viking treasures in Galloway – a sum Freeman calls “very unusual case for us.” (Out of about 60 finders that year, meanwhile, nine waived their reward.) Most are in the $15 to $10,000 range.

When she’s not identifying finds, Freeman spends a lot of time on outreach. She holds events at museums and pubs around Scotland to educate hobbyists like Stepien about the vast gap between archaeology and “nighthawking,” the term for searching without a landowner’s permission, or in national parks or other protected areas—all illegal in Scotland. “We’re trying to shift into seeing the value metal detectorists are adding to the archaeological record, or to museum collections,” she says

Stepien pausing in that field is a flicker of hope. He had never reported anything to Treasure Trove before, but thanks to friends in the community, he knew who to call.

Kneeling over the hole, Stepien and Gucwa snapped photos with their phones as Stepien brushed away more soil. The palm-sized find was metallic, but so dirt-encrusted he couldn’t make out what it was.

Over the next half hour, Gucwa watched and took pictures while Stepien lifted four more objects out of the earth. Three were D-shaped, and rounded at the edges like no coin Stepien had ever seen. When he rubbed the moist dirt away with his fingers, he could make out concentric circle patterns and what looked like bits of wood. He swore softly in his native Polish.

Stepien stopped digging, carefully lifted the stone back into place, and smoothed down the grass nearby to cover up any signs of disturbance. Buzzing with excitement, he and Gucwa snapped one last photo, carefully wrapped the metal objects, packed up their gear, and drove away. “Four things in such a small hole? That’s not normal,” Stepien recalls. “I knew we had to call Treasure Trove.”

Taking the bronze

When she opened the email from Stepien, Freeman wasn’t sure what she was looking at. But she did know the artifacts in the attached photos were old. Really old. “Most of the objects we deal with aren’t that valuable monetarily. But they’re archaeologically still significant, or we wouldn’t be claiming them,” Freeman says. “There’s a big element of decision-making: Is it rare, unique, unusual?”

At first glance, the finds checked all three boxes. A historian with two masters’ degrees and an encyclopedic knowledge of Roman coins, Freeman says they didn’t look medieval, Viking, or Roman—the most common categories of pre-modern artifacts that cross her desk.  

On a hunch, she forwarded them to Fraser Hunter, an archaeologist and curator at the National Museum of Scotland. Hunter immediately knew their green patina suggested something older still: metal from the Bronze Age, which lasted from around 2200 to 800 BCE in Scotland.

Bronze, an alloy of copper, tin and occasionally lead, and trace metals like aluminum and arsenic, is particularly exciting to preservationists because of its chemistry. As it corrodes, the bronze creates an anti-bacterial environment in the surrounding soil. That means it slows and prevents the decay of materials like leather, wood, and fabric from decay for centuries, or longer. “Organics take you into the lost worlds of the past, into things that don’t normally survive. That really is the lodestone as an archaeologist,” Hunter says. “When you ally that to the fact that Mariusz said he’d left things in the ground, I knew this was something we had to go investigate.”

Less than 72 hours after his detector first pinged, Stepien led Freeman, Hunter, and a few other archaeologists to the spot where he first found the discs. It was a sunny, warm morning, and soon the whole crew was working in T-shirts to clear turf from a 12-by-12-foot square around the site.

As the experts worked, the two metal detectorists scanned the cleared ground. Using their wands and a stubby, orange, hand-held metal detector nicknamed “the Carrot,” Stepien and Gucwa helped pinpoint the outer limits of the deposits.

They soon identified a zone three feet long and two feet wide where the signal was particularly strong. Using trowels, dental picks, and brushes, the researchers removed soil a fraction of an inch at a time, revealing the outline of more objects: first a bronze sword, then a jumble of objects like the ones Stepien found days before.

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Within a matter of hours, Hunter and Freeman realized they had a hoard on their hands— something intentionally hidden, either in the hopes of returning for it later or as part of a ritual or ceremony. The last time anything like it had been found in the area was in 1864. To Hunter, the real treasure wasn’t the metal; it was the traces of organic material he could make out among the artifacts, including a tangle of leather straps and a wood-and-leather scabbard concealing the blade of the sword.

That a farmer’s plow hadn’t torn it apart was a near-miracle, perhaps a benefit of the rocky soil. Had Stepien used a shovel instead of a brush to dig out the first few objects, or pushed deeper into the hole to pull out the metal he knew was still there, he might have done irreversible damage to the 3,000-year-old material. “You could have destroyed it in five minutes with a spade,” Hunter says. “It takes an enormous amount of self-restraint to stop. We’re really lucky they did.”

Digging out

Over the next 10 days, a remarkable find emerged from the stony Peebleshire pasture. Fraser was joined by Matthew Knight, a red-haired Bronze Age specialist at the National Museum of Scotland who was called back from pandemic furlough to help with the find. Slowly, they removed soil, pebbles, and fist-sized stones a fraction of an inch at a time, revealing the outline of the hoard.

The scabbard, it turned out, was just the beginning. Underneath, what had at first looked like a jumble of odd bronze coins turned out to be a complete horse harness, its metal tabs, rings, and buckles still attached to leather straps.

Some of the fittings were stubbornly hard to place–including the rounded pieces Stepien first pulled from the ground. After 12-hour days kneeling in the field, Knight returned home and pored through old excavation reports and museum catalogs trying to find something similar. When he figured it out, he was stunned: The fittings were part of a rattle pendant, a set of interlinked rings designed to jangle and chime as the horse walked. “It’s Bronze Age bling,” Knight says. “You’re seeing how a Bronze Age Rolls Royce looked.”

[Related: What archaeologists got wrong about ancient women.]

The find, Knight says, connects this quiet corner of Scotland to a wider world. Though virtually unprecedented in Britain, similar jangle pendants are common features of upper-class Bronze Age burials in Denmark and southern Scandinavia. Was Peebles once home to a foreign dignitary from across the North Sea, or an itinerant master craftsman? “Every now and then,” Knight says, “you get glimpses of international trade networks. We’re starting to get a picture of a community that had these connections with that part of Europe.”

Left exactly as they were buried 3,000 years ago, the finds contain information metal alone wouldn’t convey—and illustrate the gap between archaeologists and the public when it comes to the definition of “treasure.” For Knight, the real booty is the site’s organic remains, which were preserved down to fragments of the thread used to sew the straps together. “This tiny piece of string is perhaps the best thing I’ve ever found as an archaeologist,” Knight says. “The fact that we have all the organics means we can see associations–we can see how all this stuff worked.” Archaeologists knew that horses were first introduced to Britain around 1000 BCE, and now Knight had a chance to reconstruct how they were ridden, how big they were, even how their tack sounded when they trotted.

As exciting as they were, the non-metal remains posed a difficult problem. The sunny, cloudless skies the team enjoyed for the first few days of excavation quickly gave way to “traditional Scottish summer weather,” Hunter says, “sunny one minute and howling winds and rain the next.” At one point, the owner of a neighboring farm spread manure on the field upwind, suffusing the area with its stench for days.

Stepien began spending 24 hours a day in the field. He helped pile hay bales around the excavation trench to shield it from the wind. As the archaeologists worked, he shooed grazing sheep to make sure they didn’t walk across the site. Worried that the tents and daily work would attract the wrong kind of attention from locals, he bought a tent and sleeping bag and slept next to the hoard every night. He kept the nearest police station on speed dial. Gucwa, who works at an Edinburgh supermarket, joined him when he could. “We owed the place something,” Stepien says. “I felt responsible for that spot.”

Bringing it home

During the day, Knight and Hunter filled the site’s guardians in on what researchers know about Scotland around 1000 BCE—and what might have prompted someone to bury such valuable equipment. Most people lived in small farming villages with a few dozen residents. Horses and wagons were brand-new technology, available only to the powerful and well-connected. And archaeological evidence in Scotland and elsewhere in Britain suggests life was becoming more violent and dangerous. Communities started to build protected, fortified settlments; swords, shields and other military equipment became more common.

Digging in Peebles, meanwhile, slowed. Because the crumbly hide straps were threaded through the bronze fittings, every move threatened to damage the fragile leather and fabric remains. “I’ve excavated a dozen hoards, and never worked on anything as complicated and difficult,” Hunter says.

The deteriorating conditions forced him to make a tough call: spend another two or three months excavating the priceless, fragile hoard in the field, or try to encase it in plaster and lift it out of the ground in one piece, a last-resort technique archaeologists call block lifting. If they succeeded, the find could be transported to Edinburgh, where it could be safely picked apart by conservators in a lab at the National Museum.

In the end, Scottish weather made the answer clear. About two weeks after the excavation started, conditions went from bad to terrible. Alone in the dark, Stepien awoke at 3:20 AM to the sound of wind hammering the sides of his tent–and then the sound of ripping nylon as the canopy covering the hoard collapsed outside.

Soaked to the skin by pouring rain, he spent three hours trying to keep the trench from flooding and the tents from blowing away before he finally gave up. “It was Armageddon,” he says. A block lift it would be.

Preparing for the lift meant digging several feet of soil all around the hoard, leaving it sticking out like a plaster-wrapped pimple in the rocky trench. As Hunter, Knight, and conservators from the National Museum prepared for the block lift, Stepien custom-built a wood box four feet long and three feet wide for the transport.

The work revealed another clue to the find’s past. On either side were the remains of walls, indicating that the treasure was originally buried in the entryway of a dismantled building. The sword on top was pointed like an arrow towards the outside.

Many Bronze Age hoards seem to have been deliberately buried as offerings or sacrifices. Giving up or destroying so much wealth willingly must have been as much a demonstration of power as devotion. The Peebles treasure seems to be no different. “We’re seeing the hoard as an offering,” Knight says. “Something significant must have happened so that they decided to bury all this stuff. In the context of a small farming community, it’s a big deal–something like this wouldn’t have happened every day, or even every generation.”

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Today, the so-called Peebles hoard is locked in a climate-controlled lab at the museum, still in the box Stepien built for it. As soon as the pandemic allows, Knight will remove the plaster and begin to excavate it in earnest, carefully documenting the location and position of each piece as he unravels its straps–and secrets. “I’ll be working on this find for the next 10 years,” Knight says.

Finally, three weeks and a day after they first started digging, the team heaved the 440-pound block of wet soil out of the trench together and slid it into the back of Stepien’s white van. Months later, Stepien still recalls the sense of relief and pride he felt when the door closed.

On the hour-long drive to the museum in Edinburgh, he and Gucwa sat in silence, alone with the treasure one last time. For the first time in weeks, they felt a sense of calm relief. “We knew we had the most important thing in the world in the boot of the van,” Gucwa says. “We were so happy we didn’t have to worry anymore, and the treasure was secure.” It’s a sense of historical stewardship Treasure Trove and approaches like it hope will spread as Stepien and his fellow metal detectors continue sweeping fields for buried treasure.

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