Also referred to as casting plaster or plaster of Paris, this is an extremely versatile material. Used by itself, it is still the standard for making mother molds for most flexible mold materials. As a sculptural medium, plaster has what is called a "period of plasticity" where it becomes clay like for a short time and can actually be modeled or sculpted. Is easily added to in this state as well. Simply use a little sisal, burlap or polypropylene fiber to reinforce this product and you're on your way. Great for general purpose casting and mold making as well, and is even used for body casting; but be careful, it can get HOT!