Originally Posted by thedoc_

Dear All,
Thank you for you input; it is really interesting and helpful to have feedback from others. I would like to add something to the discussion; this may give a new insight to bentonite.
According to Wikipedia, Bentonite is an absorbent aluminiumphyllosilicate generally impure clay consisting mostly of montmorillonite, (Na,Ca)0.33(Al,Mg)2Si4O10(OH)2·(H2O)n. Two types exist: swelling bentonite which is also called sodium bentonite and non-swelling bentonite or calcium bentonite. It forms from weathering of volcanic ash, most often in the presence of water.

Bentonite also has the interesting property of adsorbing relatively large amounts of protein molecules from aqueous solutions.
Bentonite can be used in cement, adhesives, ceramic bodies, cosmetics and cat litter. Fuller's earth, an ancient dry cleaning substance, is finely ground bentonite, typically used for purifying transformer oil. Bentonite, in small percentages, is used as an ingredient in commercially designed clay bodies and ceramic glazes.

I have found out that it is also used in pesticide industry cosmetic industry, as a carrying agent for the active ingredients.
I have contacted the company that produces this and i was told that"Even after wetting each individual granule absorbs without dissolving and stays hard and maintains its original shape, which is a very important factor. You simply scoop away the soiled clump and top up with fresh litter. Other bentonite clays that swell and dissolve form a muddy pancake, sticking to the cat's fur and paws and litter the floor."

I am not an expert or enything but I suppose calsium bentonite (non swelling type) may be used. I will probably experiment with it.

Waiting for your comments and advice.
Thanks.
Stav.