
bentonite companies in the united states central oregon bentonite co. (l c mining company). 50500 se camp creek road, prineville or. (541) 477-3351. clay, ceramic, and refractory minerals,,bentonite mining in,bentonite and fullers earth resources of the united states3.53 . the first bentonite mining in the black hills area of wyoming began in 1897 near newcastle (heathman, 1939).there is probably a large quantity of bentonite and bentonitic clay used locally for sealing irrigation ditches and stock ponds that is not included in the u.s. bureau of mines annual...