A lightweight refractory material processed from high purity alumina-silica fibers. Withstands temperatures up to 2300 degrees F (1260 degrees C). Contains an organic binder which burns off at 1250 degrees F (677 degrees C). During burn-off the kiln and studio must be well ventilated. These reflactory fiber papers when heated above 1800 degrees F (982 degrees C) transform to Cristobalite, a form of crystaline silica, which may cause lung injury. Does not contain asbestos.