Diamond Dust Hole Saw

Diamond Dust Holesaws are suitable for drilling ceramic, glass, marble, slate, and porcelain tiles. Designed for use with conventional power drills on a slow-speed setting with no hammer action and a constant supply of water.
A real low-cost solution for drilling glass, these diamond hole saws must be provided with a constant supply of water to stop the tip overheating and breaking down the bond holding the diamonds onto the steel shaft.
We find a wet sponge held against the drill bit works really well.