Bentonite (/ ˈ b ɛ n t ə n ʌ ɪ t /) is an absorbent aluminium phyllosilicate clay consisting mostly of montmorillonite.One of the first occurrences of bentonite was found in the Cretaceous Benton Shale near Rock River, Wyoming.The Fort Benton Group, along with others in stratigraphic succession, was named after Fort Benton, Montana in the mid-19th century by Fielding Bradford Meek and F ...
