The USGS reports new American uranium potential and a new uranium “species”
by Greg Klein
The dream of discovery must motivate many a geologist. Through skill, effort and luck they hope to eventually find something precious, useful or otherwise valuable—something well known yet found in a previously unknown location. But a group of geo-boffins from the U.S. Geological Survey not only identified a type of uranium Deposit previously unknown to their country, they discovered a new mineral.
It’s finchite, “a new uranium mineral species,” as a press release described it last week. The discovery actually dates to 2015, says Brad Van Gosen, the USGS scientist who did the discovering.
While surveying a Texas cotton ranch Van Gosen collected samples of what he and his colleagues thought was carnotite, “a pretty common yellow, near-surface uranium mineral.” Back in the lab, he put it under a scanning electron microscope, which kept showing strontium with the uranium and vanadium, he recalls. To a geologist, it was unusual—very unusual. A eureka moment was looming.
“We looked it up and there’d been no strontium-uranium mineral ever reported before. So [team leader Susan Hall] worked with a crystallography/mineralogy lab that specializes in micro-analysis up at Notre Dame and they concluded, ‘By gosh you’re right.’” Further study continued before sending the evidence to the International Mineralogical Association. “They’re the high council and they blessed it as a new mineral.” Finchite’s moniker honours the late Warren Finch, a USGS uranium expert.
Another major finding was that the uranium was hosted in calcrete rock formations, a style of deposit known elsewhere but reported for the first time in the U.S.
Some previously secret info led to the twin epiphanies. Hall, as leader of a project that’s reassessing national uranium resources, gained privy to some unpublished 1970s and ’80s data from the former Kerr-McGee company. Included were estimates for two deposits, Sulphur Springs Draw and Buffalo Draw, with marginal grades of 0.04% and 0.05% U3O8 respectively. Together they held an estimated 2.6 million pounds U3O8.
(Of course data from historic sources and the U.S. government agency falls outside the framework of NI 43-101 regulations.)
The newly transpired, near-surface deposits led Hall and her group to the Southern High Plains spanning parts of Texas, New Mexico and Oklahoma. It was there that they recognized calcrete, its first known manifestation in the U.S.
The stuff’s associated with uranium in other countries. Among major calcrete-style deposits listed by the World Nuclear Association are Yeelirrie in Western Australia, along with Trekkopje and Langer Heinrich in Namibia. Yeelirrie is a potential open pit held by a Cameco Corp TSX:CCO subsidiary and averaging 0.16% U3O8. Trekkopje, a potential open pit majority-held by AREVA Resources, averages 0.01%. Langer Heinrich, an open pit mine operated on behalf of Paladin Energy, the majority owner now under administrative control, averages 0.052%.
According to the USGS, grades for potential Southern High Plains deposits range from 0.012% to 0.067%, with a median 0.034% U3O8. Gross tonnage estimates range from 200,000 to 52 million tonnes, with a median 8.4 million tonnes. Together, the region’s calcrete-style potential comes to 39.9 million pounds U3O8.
But that’s a regional assessment, not a resource estimate, reflecting how USGS methodology contrasts with that of exploration companies. The agency uses a three-part approach, explains Mark Mihalasky, who co-ordinated the assessment. The procedure first delineates areas that would allow the occurrence of a particular kind of deposit. Using additional geoscientific evidence, the agency estimates how many deposits might be awaiting discovery. How much those potential deposits hold can be estimated through comparisons with similar known deposits around the world.
Mineral assessment and mineral exploration are two different things…. It’s not a ‘drill here’ assessment.—Mark Mihalasky
“Mineral assessment and mineral exploration are two different things,” Mihalasky emphasizes. “The purpose of our assessment is to help land planners, decision-makers and people in the region get an idea of what could be there, based upon probability. It’s not a ‘drill here’ assessment.
“This whole region is a relatively newly recognized area of potential and while we’re not saying this is a new uranium province we are saying there’s something here that hasn’t been found before in the United States and this might be worth looking into in greater detail if you’re an exploration company.”
Already one company from Australia has been asking “lots of questions,” says Van Gosen. Although most uranium mining in the American west uses in-situ recovery, the shallow depth and soft host rock of the Southern High Plains could present open pit opportunities “assuming uranium prices and other factors are favourable.”
Any positive price assumption will have to wait, however. One week earlier Cameco announced the impending suspension of its high-grade McArthur River mine and Key Lake mill in Saskatchewan’s Athabasca Basin. The company said that long-term contracts had shielded it from uranium’s post-Fukushima plunge of over 70%, but those contracts are now expiring. Cameco had previously suspended its Rabbit Lake mine and reduced production at its American operations.
But while production faces cutbacks, controversy over American dependence on foreign uranium flared up again last month with renewed questions about the sale of Uranium One to Russia’s state-owned Rosatom. The formerly TSX-listed Uranium One holds American resources that could potentially produce up to 1,400 tonnes of uranium annually, according to the WNA. But last year the company’s sole U.S. operation, the Willow Creek ISR mine, produced just 23 tonnes of the country’s total output of 1,126 tonnes.
As the world’s largest consumer of uranium for energy, the U.S. relies on nukes for about 19% of the country’s electricity, according to USGS numbers. Only 11% of last year’s uranium purchases came from domestic sources.