The first faceted eosphorite, a member of the childrenite-eosphorite series, is seen in the Carlsbad lab.

Material submitted as a rough diamond is revealed through gemological testing and analysis to be a near-colorless topaz.

A Fancy orangy yellow “cape” diamond featured an unexpected 480 nm band, a defect normally associated with orange color.

Examination of a diamond with a rare and highly sought-after Fancy reddish brown color revealed that it had been irradiated and coated.

Reports on the internal features and spectroscopic and trace-element analysis of sapphires reportedly from Badakhshan, Afghanistan.

Scientists and gem experts shared the latest research and studies on gemstones at the Geological Society of America annual meeting in Denver.

The first example of a lead glass–filled black star sapphire examined at GIA’s New York laboratory.

The first sapphire with green lead-glass filling examined at GIA’s Carlsbad laboratory.

A type IIa color-treated diamond was graded as Fancy brown-pink under daylight conditions and Fancy purplish gray under incandescent lighting, a color change that resulted from HPHT annealing and irradiation.

Examination of a 59.88 ct irradiated yellow diamond, one of the largest irradiated diamonds identified by GIA.

An iridescent Japanese andradite contained an iridescent inclusion of andradite, creating an arresting optical phenomenon.

A rough colorless beryllonite showed an unusually sharp separation between two regions, caused by minute inclusions deposited during growth that prevented growth of the host mineral.

A striking aquamarine specimen showed a strongly saturated secondary growth layer.