The Gemological Institute of America (GIA) has detected a natural 0.33-carat Type Ia white diamond with a synthetic, Type IIb synthetic layer applied on top to color it a fancy blue, according to Gem Konnect.
According to the GIA, its New York laboratory “was alerted by the fact that it saw both nitrogen and boron defects in a single diamond”. This is the first time that the GIA says it has seen a synthetic overgrowth on a natural diamond with a fancy color grade.
The GIA cautioned that “identification of colored diamonds should be performed very carefully by looking for unusual characteristics, such as a straight boundary line associated with an interface plane, and fluorescence zones with sharp edges in DiamondView images”.
