One of my mentors from the 1970s, a co-inventor named on my first patent, co-owned/started their own clay mine 25+ years ago.
He was a millionaire when he past away 3 months before Covid19 started, millions made from profits off the products he made for specialty environmental market applications. I learned a lot from him about real world industrial technology, and processes decades ago, 1970s and 1980s, when I was just a Padawan learner. Then I got my Bio-Chemical/Environmental engineering degrees and US DOE grants in the early 1990s... (Yes I too am getting old, but still have much good tread on my tires LOL)...
This firm here is the real deal. And if they find the right target markets for their clays, or set up and process the clays to meet the right market needs, they could become insanely profitable.