a porous clay consisting mainly of the mineral montmorillonite, which swells greatly when it absorbs water
Origin of bentoniteafter Fort Benton (named for Senator Benton) in Montana, where it is found
An absorbent aluminum silicate clay formed from volcanic ash and used in various adhesives, cements, and ceramic fillers.
Origin of bentoniteAfter Benton Formation of the Rock Creek district in eastern Wyoming
From Benton + -ite, after the place it was first mined: Fort Benton, Montana.