Question: what is the difference between bentonite and montmorillonite clay?
Answer: Montmorillonite clays and Bentonite clays are one and the same thing. All types of Bentonite clays are grouped together under the Montmorillonite or Smectite group of clays. ... Montmorillonite, a phyllosilicate, is a soft type of mineral that exists in small crystals which accumulate to form clay.