I need to drill or cut a decent size hole in a piece of slate which is 2 foot by 2 ft, and about 1 1/4" thick. The hole can be as small as an inch or as large as 6 inches square (it gets covered).... I have nightmares of taking a hammer drill to this thing and having it crack. It's pretty solid, but still.... One thought is to just use a masonry blade on my circ saw and lower it slowly into it. But this might be very slow. Am I being too careful - should I just use a small hammer drill and perhaps drill 3 or 4 small holes next to each other to make a larger hole?