Clarity Enhanced Diamonds — Should You Buy a Treated Diamond?
Clarity treatments for diamonds and the pitfalls of buying a clarity enhanced diamond
What are clarity enhanced diamonds?
Clarity enhanced diamonds are natural diamonds which undergo a treatment process to artificially improve clarity in the diamond.
The treatment process typically falls into two main processes. Firstly laser drilling and secondly fracture filling. Both treatments aim to reduce the appearance of natural clarity characteristics within a diamond.
Laser drilled diamonds
Laser treatments involve drilling a fine laser hole through a diamond. This process burns away an internal inclusion. The laser hole allows access to bleach deep inclusions. As a result, the diamond benefits from enhanced clarity and an improved appearance. The image below, courtesy of the Gemological Institute of America shows the drill-hole under high magnification.
Laser holes can be very difficult to see, even with a trained eye. Under 10x magnification, we look for small holes on the surface of a diamond. From these holes, fine hair-like lines extend into the diamond as shown here.
Fracture filled diamonds
Fracture filling improves the appearance of a diamond’s clarity. In this treatment process, a glass-like resin is injected into the diamond. The resin fills visible feathers. Just like laser drilling, this treatment can be very hard to identify, even to the trained eye. Some diamonds treated this way exhibit a flash of purple or green owing to the differing optical properties of the resin.
Fracture filled diamond (before — left) and after treatment (right)