The stunning iridescence of opals is best highlighted in a ring setting. However, these fragile gemstones are in jeopardy of crazing and chipping due to mistreatment and exposure to the elements. Crazing occurs when an opal experiences sudden extremes in heat or cold, causing a crack to appear on the surface of an opal. Chipping and scratches occur when your opal contacts hard surfaces with force. Prevention is the best measure, but depending on the type of damage, a jeweller may be able to repair the opal by repolishing it or using a polymer impregnation process.
Take your damaged opal to a professional jeweller if you do not have the proper tools or polishing wheels.
Identify the location of the chip, scratch or crack on the opal.
Remove the opal from the ring, using the jewellery tools, and place it on the dop stick, which will hold the gem in place while polishing.
Polish the opal with the 600-grit wheel. Polish in a twirling motion to smooth the larger scratches and chips from the gem.
Create a smooth, fine finish with the 1200-grit wheel. Again, polish the opal in a twirling motion until it gleams.
Remove the opal from the dop stick, and return the opal to its setting in the ring using the jewellery tools.
Impregnate the gem with polymer resin if the opal is crazed. The polymer will strengthen the stone while avoiding further damage. Polymer resin is a high-gloss, plastic varnish, which is carefully injected into the cracked portions of the opal. It is clear, which allows the natural iridescence of the opal to shine.
Polymer impregnation is best completed by a professional jeweller who has the necessary skill and equipment.
Due to the challenging nature of opal repair, it is best to consult a jeweller who has experience with porous gemstones.