Laser is a new technique for cleaning and decorative machining of natural stone, which is a brittle material. Copper vapour laser (CVL) is a suitable tool for machining without damaging the work material. Thus, this technique is suitable for the machining of different materials such as natural stone, ceramic and wood. In this study, the comparative modification of marble, serpentine, quartzite and granite with CVL technique has been investigated. Encouraging results are obtained with marble in all applied laser power ranges and in serpentine in the low power range. (C) 2002 Published by Elsevier Science B.V.