Sorry the link isn't working. See below for description. It says its a montmortilite clay.

Use granulated Safe T Sorb⢠Oil Absorbent to absorb liquids, including most types of oils, mixtures or soluble oils and water, acids, paints, inks and water.
100% natural earth clay product processed to a granular form

Highly absorbent granules are made of non-flammable minerals
Can reduce hazards and slipping accidents
Helps prevent flash oil fires
Keeps floors clean and dry
For use in work or home environments
Water Absorbency (Weight) - 79%
Easy to use and transport
Environmentally friendly