X-ray data and other ceramic properties such as expansion, weight loss, specific gravity and apparent porosity of the kyanite obtained at various temperatures are presented. X-ray studies gave the most reliable method for the determination of kyanite and mullite, the end product of kyanite Laboratory investigations indicated that kyanite is suitable as a refractory material to be used in high temperature boilers, in cement and ceramic kilns and in metallurgical and glass furnaces.