A swath of northeast Minnesota has long been called the iron range, but some prospectors are hoping it might someday be known as the gold range.
Officials with the state Department of Natural Resources have found promising results in tests from soil near Tower and Soudan pointing to possible gold in bedrock there.
The samples contained an encouraging number of tiny gold grains that are rough, meaning they likely originated from a nearby source. Smooth grains indicate that they were worn smooth while traveling in glacier movement. Though the discovery is still a far cry from finding actual gold deposits, officials warn, it’s also not surprising to geologists who have long suspected northern Minnesota is golden.
“Particularly when we’re considering gold potential, the bedrock in northern Minnesota is the same bedrock units found across the border in Ontario,” said Don Elsenheimer, an economic geologist with the DNR. “On the Canadian side, there are dozens of active and past producing gold mines.”
It’s been harder to find the gold deposits in Minnesota, though, because it has fewer outcrops or spots where rock sticks out on the earth’s surface.
In addition, the gold deposits in that type of terrain are typically vertical, possibly extending 2,500 or 3,000 feet deep, making them difficult to pinpoint on the surface, Elsenheimer explained.
So geologists are collecting sediment instead to see if there are tiny grains of gold that are rough and plentiful.
In typical 2-gallon-bucket samples of soil around the state, each about 20 pounds, experts may typically find one gold grain.
In 17 samples taken in spots southeast of Tower-Soudan recently, 15 contained more than 10 grains each, most of them rough.
Elsenheimer let out a whoop in his cubicle office when he learned of the test results.
“They came back higher than what you would expect and high enough to be considered kind of interesting,” he said, quickly adding caution: Finding the grains is a long way from finding gold deposits.
Elsenheimer likened it to standing in a hay field with 100 haystacks in front of him and determining that a couple “have a high potential for containing a needle.”
“These are great results,” he said, “but there’s still a lot of work that would have to be done to determine if there’s something to come from this.”
History of gold
The testing was done by the DNR on part of 12 million acres of state-owned mineral rights, 3.5 million of which are part of a trust fund for the benefit of schools throughout Minnesota.
“We have an obligation to generate revenue from the trust lands and to manage all of the trust lands in a way that is consistent with state priorities,” Elsenheimer said.
Northern Minnesota isn’t unfamiliar to gold prospectors. In 1865, tiny amounts of gold were found embedded in quartz in what the DNR now calls the Vermilion Lake gold rush. Mining wasn’t profitable, though, and prospectors left by 1867.
In the 1890s, miners settled in communities along the Canadian border, including International Falls, in a short-lived gold rush that contained the state’s only productive gold mine, the Little American Mine.
Mining for gold eventually led to the discovery of the Iron Range, which proved much more profitable.
In recent decades, a number of companies have been actively exploring for gold, with prospectors leasing some state-owned mineral rights, hoping to strike it big.
Rick Sandri, president of Minnesota-based Vermillion Gold, said his company is already exploring in scrub fields west of the Soudan area.
Most states have gold in them, Sandri said, but finding enough worth the expense of mining is the tricky part.
“You can find gold just about anywhere … finding a gold mine is extremely difficult,” Sandri said.
As a company, Vermillion isn’t interested in exploring for the potential deposits that the DNR just discovered near Soudan, Sandri added.
Private land owners who have cabins or property in the wooded area also make exploration complicated.
“We don’t want to spend half of our budget worrying about land negotiations and lots of issues that will come up at some point if somebody finds something,” he said. “We have, as a corporation, taken that as an attitude. Other people might not.”
Environmental groups aren’t so excited about the prospect of gold, though.
The precious metal may be embedded in rock containing high amounts of sulfide, they point out, possibly leaving a toxic byproduct if mined.
One possible extraction method for gold is to crush rock and separate the heavy gold pieces by letting them sink in water.
The water could contain sulfide, however, and environmentalists say there’s no guarantee that won’t get into streams and lakes.
Other methods include using chemicals to separate gold from waste rock.
“There should be a moratorium placed on any sulfide mining while we stop and evaluate … how they’re going to clean that up,” said Elanne Palcich, of Save Our Sky Blue Waters, which opposes efforts to mine the region for copper and nickel for that reason.
The newly discovered grains were found not far from the new Lake Vermilion-Soudan Underground Mine State Park, as well as nearby Bear Head Lake State Park.
Palcich said she sees the DNR’s role as conflicted.
“One part of the DNR is putting in a state park and the other part of the DNR is wanting to mine,” she said. “That just doesn’t make sense.”
Elsenheimer said gold mining operations won’t take place in the state unless environmental impacts are addressed and mitigated.