Abstract
Tuff is a soft natural stone of low strength being composed mainly of alumina, silica and iron oxide. Since it's surface fails to produce any luster by mechanical polishing. The use of tuff had hitherto been limited to warehouse walls, fences, and so on. Laser treatment produced a white ceramic layer over most of the surface. At the same time, iron rich areas, commonly referred to as “MISO”, were turned black, resulting in an external appearance resembling “INADA”granite stone. The ceramic layer thus obtained is comprised of minute glass bubbles that impart luster to the surface. The surface luster was improved as desired by altering the laser treatment conditions. These results suggest that laser treated tuff can be used as a novel architectural material for interior decoration.
