You rule. Thank you for all the wonderful info!Date: 8/25/2007 10:08:34 PM
Author: JohnQuixote
The AGS and GIA labs will both grade laser drilled diamonds. The fact that it was laser drilled will be noted on the grading report, per FTC requirements. Neither lab will accept fracture filled diamonds (a treatment sometimes done after laser drilling).
Laser drilling was developed in the 1980s. An infrared laser is used to bore fine holes into a diamond in order to selectively target and remove inclusions, or reduce their visibility. This improves the diamond’s apparent clarity grade. After the inclusion is reached by the boring laser the diamond is placed in sulfuric acid to dissolve the target crystal or staining. Sometimes an inclusion within a diamond is a diamond itself and not vulnerable to this process.
The diamond material removed during the drilling process is often replaced with glass infilling, called ''Fracture Filling.'' This was also developed in the 1980s, by a company called Yehuda, but did not become common until the 1990s. In this process small cracks, or feathers, in a diamond are filled witha molten, glass-like resin that has the same optical properties as the diamond. This makes the cracks almost invisible to the eye and improves the diamond’s apparent clarity grade. The weight and color are not affected, but you can often see this type of treatment in what is called the ''flash'' effect: When the diamond is tilted back and forth there are unique color changes that occur in a flashing manner.
The reason the AGS/GIA labs will not accept fracture filling is because it is not a permanent treatment - there is the possibility the filling could fall out. Repeated cleaning, re-polishing or repair procedures for jewelry that expose the diamond to heat might damage or remove the filling. There are companies other than Yehuda offering treatment, but Yehuda is best known and historically offers the strongest guarantee: If the treatment is damaged or falls out they will fix the diamond for free.
Some companies will not deal in clarity enhanced diamonds (the company I work for is one of them) but this doesn''t mean they are ''bad.'' Clarity enhancement may allow a buyer to get a larger, cleaner diamond than he/she could normally afford if he/she is ok with it.