Refractory grog are pulverised particles from firebricks used in clay body formulation to reduce greenware fired shrinkages. Mainly used in high fire ceramic clay body formulation like stoneware clay not exceeding 10-20% to clay content. Its coarse grit 80 to dust add tooth character to stoneware throwing. Color might vary from grey, brown to dark brown depending on the fire brick composition and firing temperature.
A low cost abrasive material for sand blasting, etching and rust removal.
As an annealing material to slow down cooling of metal knives, tools steel for further working in soft state.