Most of the time a laser beam passes through a clean, clear diamond and nothing happens. However, there are times when the laser beam hits an impurity and a burst occurs, like in the diamond shown here. For this reason, I no longer use a laser to re-tip over expensive diamonds or coloured gemstones, although for melee, it is a viable option. The savings in time and materials outweigh the inevitable loss of a stone or two. Stone damage occurs approximately one per cent of the time.
Tom Weishaar is a certified master bench jeweller (CMBJ) and frequent speaker on jewellery repair topics for Jewelers of America (JA). He can be contacted via e-mail at email@example.com.