An interesting recent project was a restoration of a sapphire and diamond three stone ring; over 100 years old, the claws had worn away, and the sapphire had become scratched. Although sapphires are exceptionally strong and tough, over a lifetime they can become scratched. In this case, long time wearing had scratched all of the facet edges, and the claws had worn out.
The sapphire was removed, and re-faceted. This totally transformed the stone, allowing the true colour to come through. It is now a totally different colour, deeper and more intense. It was re-set, the claws restored and the band of the ring repaired.
All in all a totally transformed ring!