Dremels are hobby level tools and they work with very high RPMs. High RPMs aren't the best thing for lapidary work, too easy to burn out material and bits. A good quality flexible shaft machine is a better idea for lapidary work since they have more torque at lower RPMs. You gotta be careful about breathing any dust or spray when working on rocks so a good respirator and face shield or goggles are also needed. Most of the carving of stones across the world is done with a small lapidary lathe and the work is fed into the bit, rather than applying the bit to the work as with a dremel or flex shaft. It is easier to keep the material cooled by water with a drip feed that way.
