Quote Originally Posted by kcb5150 View Post
I have a green I had selected and cut from a quarry years ago. It works fine. I wouldn't use slurry on it. The purple does sharper but not quite as smooth as the green in my experience and there is a streaky black type that makes the sharpest edge for me by far. You just need to make sure you get pieces with no crystalline weirdness going on.
which quarry?