Bentonite water absorption characteristics
Wyoming bentonite can absorb up to 7 to 10 times it's own weight in water.

Wyoming bentonite is composed essentially of montmorillonite clay, also known as hydrous silicate of alumina. In more simplistic terms, the structure of bentonite is much like a sandwiched deck of cards. When placed in water, these cards or clay platelets shift apart. Bentonite attracts water to its negative face and magnetically holds the water in place. because of this unique characteristic, Wyoming bentonite is capable of absorbing 7 to 10 times its own weight in water, and swelling up to 18 times its dry volume.