Spear-point carbide bit works fine for me. Make a starter hole with a
carbide-pointed scribe or other small tool, using a small hammer. They are
sometimes sold as "glass and ceramic drill bits". I got mine at Home Depot.

"Chamblin" wrote in message
oups.com...
We need to drill porceline tile to attach a handicap rail to wood
blocking placed in the wall.
Carbide bits will drill through most tiles, but not porceline. I have
tried.
Tile companies state that diamond bits are needed, and must be used
with water.
Anyone experienced with this process? Where can these be purchased?