Purchased to cut sea glass for projects. It does this very well. Takes between 7 and 25 seconds depending on the thickness of the glass. I use a Dremel 3000. The bits fit a standard chuck size. The beat also popped through several thin shells in about two seconds. So far I've made two shells and 12 pieces of glass on the first hit. If I had to guess I'd say that approximately 40% of the resource remains in the drill.