Activ-Clay is an air drying clay, which is fine grained to enable the finest detail for all arts and craft projects. This strong, self-hardening clay is perfect for all levels of sculptors, as it allows for many clay sculpting techniques from hand building to throwing, and accepts a wide variety of finishes. Activ-Clay can be carved, nailed and sanded. This natural clay generally dries within 24 hours with minimal shrinkage, and can be kept for weeks when placed in an air tight container.