Lithium Mines for the Scientifically Illiterate - The Freelance Files MMCCLXXX

smectite vs. illite

One of the staffers was browsing the default newsfeed on her phone while her S.O. binged some Star Wars spinoff when an article about a potential source of lithium caught her eye. Thinking he might be interested in the info, she forwarded the URL to the staff geologist. Once he woke up from his nap, S. G. read the "information" with increasing horror. Oh, sure, freelancer Bob Yirka managed to get a few things right; such as the importance of lithium to the modern economy and the location of the apparent deposit, but as for the rest of "New evidence suggests McDermitt Caldera may be among the largest known lithium reserves in the world" (at phys.org)? Naahhhhhhh.

Back in the earliest days of the internet, long before Insta photos of avocado toast or tweens dying from TikTok challenges, a "master" of UseNet called himself "the Great KIBO," an acronym for "Knowledge In, Bullshit Out." How prescient! because Yirka's post is a classic example of KIBO. Fortunately, he included a link to his source material, so S.G. could see where this dumbassery entered the process. It was not with the three scientists who published the material... 

As we noted before, Yirka appears to have satisfactorily answered the questions of what, when, and where. It's in his attempt to transcribe the "how" that Bob fell down on the job. Here are his own words:

"Their theory posits that after a volcano erupted (creating among other things, lithium), a hydrothermal enrichment occurred—magma deep unground pushed its way to the center of what is now the caldera, leading to the formation of the Montana Mountains. As that happened, faults, fissures and fractures were created, allowing lithium to seep up toward the surface. This process also transformed much of the smectite into illite (different forms of clay minerals), which wound up along the southern rim of the basin. That, they conclude, explains why lithium is so abundant there."

Let's unpack that, misstatement by misstatement:

This volcano did not "create" lithium (or any other element). Instead, heated fluids (that's what "hydrothermal" means) preferentially enriched certain minerals in the surrounding rocks and/or sediments in lithium; in this case, clay minerals in lakebed deposits. The lake-bed claystones, much of which derived from alteration of volcanic ash, were already rich in lithium. Lithium did not "seep up toward the surface": lithium is a solid metal. Instead, hot fluids rich in lithium (among other elements) moved through the surrounding rock. Bob got this much right: smectite and illite are "different... clay minerals." On the other hand, we're at a loss to explain how smectite, once converted to illite, could migrate to the southern rim of the basin. Apparently, Bob didn't understand that this transformation occurs in place...

• Yirka missed the point: lithium is abundant in claystone deposits throughout the caldera, in part because much of the section is sourced in the ash and other ejecta of the same volcano. The hydrothermal process further enriched smectite deposits as they transitioned to illite with exposure to higher temperatures.

Freelance "journalism" like this is why the Great KIBO was right, and why we still hand out new Dumbass of the Day awards. Feh.

SI - VOLCANOES