Large HPHT-Treated Fancy Pink Diamond
The New York lab encountered another large HPHT-treated diamond that showed stronger pink colouration.
Stellate zircon inclusions in vivid purple-pink morganite
Zircon clusters and other inclusions help to create an unusual vivid purple-pink morganite specimen.
Round CVD Synthetic Diamond Over 1 Ct Identified in Hong Kong Lab
Advances in CVD growth technology have resulted in crystals that yield well-proportioned round brilliant cuts.
CVD-Grown Synthetic Diamond with Aggregated Nitrogen Impurities
Recently, an unusual 0.94 ct Fancy yellow-brown emerald was submitted to GIA for a synthetic diamond grading report. It contained a cloud of black needle-like inclusions occurring along a plane and showed weak green transmission with fibre-optic illumination.
CVD Synthetic Diamond with Unusual DiamondView Image
Deep blue fluorescence in a CVD synthetic diamond mimics patterns found in natural specimens.
Turquoise with Fingerprint Pattern
A fingerprint pattern, possibly left by human skin oils during the assembly process, is observed in natural turquoise beads.
The first documented UV-reactive chemical treatment to make opal appear tenebrescent.
Assembled “Pearl” Filled with Wire
Microradiography reveals wire fillings within a “pearl” created from two separate specimens.
For the first time, GIA's laboratory has examined tanzanite colour-coated with titanium.
Green Diamond Treated with Radioactive Salt
The stone owes all of its green colour to these shallow radiation stains.