A powdery solid used as an abherent and mold-release agent in the plastics and rubber industries. Typical materials in general use are talc (soapstone), mica, slate, flour, and clay. Graphite and mica have a flat, crystalline structure which causes them to act as lubricants, and thus are especially effective in preventing sheets or slabs of hot solid mix from sticking together when stacked.See Antiblock Agent.