Limestone is mined in various stages. First the top soil is bulldozed or shoveled out till you reach the hard rock. Then is cut into block any where from 20 tons to 4 tons. There are 3 grades, top ledge, bottom ledge and middle. There is a soft line in the middle portion that also is the fossil line. The blades that custom cut for the basic user is made out of diamonds on a heavy rubber bands.