Move over iron ore, copper, gold and titanium, there may be a new mineral for Minnesota swoon over.
The state Department of Natural Resources this week quietly revealed it has been looking for lithium in rock samples taken near Orr, north of the Iron Range.
So far they're not sure how much they found. But if early hunches are accurate, several of the region's geological formations may hold lithium - the uber in-demand mineral in batteries powering the communications and green-technology revolutions, in everything from cellphones, laptops and electric cars to giant storage units for wind and solar generators.
Prices for processed lithium have soared in recent years, from $1,500 per ton in 2002 to nearly $20,000 today, more than doubling in the past two years.
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Minnesota is late to the game, with Australia, Argentina, Bolivia and Chile now producing much of the world's supply. Nevada already is in the grips of a lithium boom with prospectors and mining companies scrambling toward production.
Still, Minnesota geologists hope to get in on the action. In recent months DNR geologists used laser-induced breakdown spectroscopy and electron microprobe analyses to check for lithium in rock samples taken last year. That data is now available online for anyone to peruse.
"Until this project started, there has not been a program to systematically evaluate the potential for lithium in Minnesota on state-managed mineral rights," the DNR noted in unveiling its lithium webpage .
Lithium has long been used in ceramics, glass, lubricants, refining metals during the casting process and in creating lightweight metals for airplanes and space vehicles. But the fastest growing use is now in batteries.
Globally, only about 38,000 tons of lithium are produced annually, according to the U.S. Geological Survey, most of it taken from underground pools of saltwater, or brine. Lithium "mining" often consists of pumping that brine above ground and using settling ponds or electrolysis to separate the lithium from the liquid.
The DNR says there are huge areas of those briny aquifers under parts of Minnesota, including an arc paralleling the North Shore of Lake Superior, roughly from Duluth up into Lake and Cook counties. There might be also be lithium in some clay deposits and in a recently discovered mineral called jadarite. Lithium has been confirmed near Lake Nipigon in Canada in a rock formation called the Quetico Subprovince. That same rock deposit crosses the border into Minnesota, from northern St. Louis and most of Koochiching counties into Beltrami County - including Orr, where the DNR samples came from the surface of state school trust fund land.
The DNR notes that some lithium had previously been confirmed in Lake of the Woods County, in the Northwest Angle. But there's probably more in other areas because "most of Minnesota has the right kinds of geology to find lithium in granitic pegmatites, brines, and in clays."
But is there is there enough lithium in Minnesota to consider mining the stuff?
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"We found a little ... but not much. What we found is probably better for telling us what direction to look next," said Andrea Reed, mineral resource geologist heading the DNR lithium project.
Larry Zanko, geological mining engineer at the Natural Resources Research Institute at the University of Minnesota Duluth, said lithium offers great potential wherever it's confirmed in large quantities that are easily mined.
"It's been out there for a while that this is around. But with the advent of lithium battery technology, the interest has really gone up," Zanko said. "Whether it's here (under Minnesota) in the concentrations needed to make it economic, we don't know yet."
The DNR is under orders to find and promote development of minerals on land where the state owns the mineral rights, especially school trust lands. The DNR is hoping that, if it finds significant amounts of lithium, an enthusiastic mining company will lease the mineral rights and look harder, eventually mining the stuff and paying millions of dollars in royalties and taxes to the state while creating jobs along the way.
Add lithium to the fast-growing list of minerals that geologists say may be worth mining in Minnesota.
Iron ore has of course been mined here for a century, and several companies have found valuable and mineable deposits of copper, nickel, platinum and palladium north of the Iron Range, namely PolyMet and Twin Metals. Kennecott has found a major copper deposit in Aitkin and Carlton counties. Two companies are homing in on major gold deposits near the Koochiching-St. Louis County border. And in May scientists from the Natural Resources Research Institute of the University of Minnesota Duluth said they had successfully turned an abundant Minnesota mineral called ilmenite into valuable titanium in a pilot-scale demonstration project on the Iron Range.
