Available in sizes from 0.75mm - 3.00mm. Straight shank.

These are like regular twist drills but coated in diamond grit, making them suitable for use on hard materials such as stone, glass, ceramics, porcelain, and shells. They are designed for enlarging holes rather than drilling holes, making them perfect for enlarging holes in pearls. 

They have diamond grit running along the tip and sides allowing them to remove material horizontally as well as vertically. They are especially good for widening existing holes. Try them on your beads.

They are used by lamp workers and bead jewellers and by many industrial companies for ceramics. If you need to de-mist your double glazing, try using a 3mm twist drill in the corner at the bottom. Magic!