Diamonds and gemstone treatments or enhancements refer to the way some gems are altered or treated to improve their appearance or durability. The effects of some treatments may lesson or change over time and some treated stones may require special care. Sometimes, enhancements affect the value of the stone.
Some common treatments and their effects include:
- Heating can lighten, darken, or change the colour of some gems.
- Irradiating can add more colour to coloured diamonds and certain other stones.
- Impregnating some gems with colourless oils or wax masks a variety of imperfections, hides cracks, and improves colour.
- Fracture filling hides cracks or fractures in gems by injecting plastic resins into the cracks.
- Diffusion treatment adds colour to the surface of colourless gems; for some gems, the center of the stone remains colourless.
- Dyeing adds colour and improves colour uniformity in some gems.
- Bleaching lightens and whitens ivory and pearl.