Redart is an earthenware material that fires red and is fired to low temperatures (cone 06-3). It has low plasticity and low shrinkage. In clay bodies, it needs bentonite added to impart more plasticity. This material makes a good casting slip but may also need the addition of bentonite to help it pull away from the walls of the mold without tearing.
Information gathered from Digitalfire Ceramic Materials Database.
50# bag; red bag, yellow text Redart with green tree