What is the difference between activated attapulgite and zeolite?

Clays: Attapulgite is the familiar keopectate which is helpful for diarrhea. Something marketed as "zeolite" (for example, for cancer) is more likely to be a health fraud -- a few years back, there was a multi-level marketing scheme in "social conservative" circles in which a drop of the stuff in a water-softener was sold for $100/ounce as a phony cancer remedy.