Gray Air-Dry Clay with Fiber. Our air-dry clay is a self-hardening clay that has no need to be cured in an oven or a kiln. Suitable for slab, coil or even wheel-thrown projects. May be finished with paint, stain, or with gloss fixatives. It will completely harden in a few days and is not food safe or good for containing liquids.
This clay contains fibers that aid in strength while helping to reduce shrinkage to 1-2%. 
No kiln firing. 10x hard than greenware. Non-toxic.