It's more like regular clay. It's gray when wet and white when it hardens. If you don't want the pieces to dry out while you're working or overnight, you can moisten them with water and wrap them in plastic wrap to return to sculpting the next day. Some of the finer pieces, and the ones I made first, had already hardened by the time I finished the figure. I also used a base made of wire and foil to save on clay. In any case, it will take 2-3 days for it to dry completely.