bentonite
/ˈbɛntənʌɪt
/noun [mass noun]
A kind of absorbent clay formed by breakdown of volcanic ash, used especially as a filler.Sedimentary rocks such as mudstones often contain a variety of clay minerals, including swelling clays such as bentonite....
- I work with a low-fire clay body consisting of ball clay, talc and bentonite.
- Three types of soils, residual soils, kaolinite and bentonite, were used in the study.
Origin
Late 19th century: from the name of Fort Benton in Montana, US, where it is found, + -ite1.