Black Hills Bentonite (Sodium Bentonite)

Sodium bentoniteoutcroppings in Wyoming.

Blue areas indicate outcroppings of sodium bentonite in Wyoming.

Bentonite is considered the product of 1000 uses. But what is bentonite? What makes it so unique? The answer to these questions started over 100 million years ago. During the cretaceous age, volcanoes in the Yellowstone area of Wyoming were subject to long periods of eruptions. Ash falling from these eruptions dropped into seas which covered much of Wyoming, forming a sediment as much as 50 foot deep. These sediments were slowly altered into the clay we know today as bentonite. In these deposits are contained 70% of the world's known supply of western or sodium type bentonite.