Review on DiamondSure Granite Ceramic Porcelain Cutting Tools with Diamond Technology by Calvin Chavva

Used for drilling porcelain bases as pilot holes for TAPCONS. Using water as a lubricant, this drill bit drills fast. The remaining depth was made with a standard hammer drill and a TAPCON drill. I found that TAPCONS had to be carefully installed since porcelain is harder than concrete, so I drilled the top 1/4" into porcelain before installing the TAPCON screw. Ordinary carbide drill bits will not drill porcelain. It looks like like the diamond head is ready for more holes.