A diamond ring from a claw game in Japan is analyzed.

A combination of growth and dissolution features contribute to a yellow diamond’s unique shape.

A study analyzing the thermal behavior of the 3161 cm^–1 IR feature in 10 natural corundum samples from various deposits.

Examination of four heart-shaped pearls reveals cavity filling and plugging to improve durability.

Examines samples of Mona Lisa turquoise to identify their chemistry and structure, revealing copper as a major elemental component of the material.

An eight-rayed star peridot with a star system made up of two different sets of inclusions is described for the first time.

GIA’s Tokyo laboratory examines three grossular garnets displaying six-rayed black inclusions arranged in a snowflake-like pattern.

A 2.50 ct natural type IIa/IaB diamond submitted to the Dubai laboratory shifts to type IIb after deep-UV excitation.

Organic-rich material is observed through an opening in a hollow natural pearl.

A 37.41 ct natural rough diamond with distinct pink and colorless zones is examined at GIA’s Botswana laboratory.

Examination of a Fancy Deep brownish orangy pink diamond reveals evidence of treatment to enhance its color.

A 63.17 ct dumortierite rough crystal is examined in the Bangkok laboratory.

The Carlsbad lab receives a laboratory-grown colorless sapphire with weblike fractures containing concentrations of dye.

Clusters of micro-inclusions form starburst-patterned clouds in a 2.50 ct Faint yellow-green round brilliant diamond.

Natural pearl cores are used to simulate the appearance of natural pearl growth in two assembled pearls mounted in a pair of earrings.

Investigates the morphological changes of macle diamonds during the growth process by exploring their three-dimensional internal zonal structure.

Investigates deposits known for producing multiple gemstone species and the conditions that create their distinct geological settings.

A photo tour of the GIA Museum’s latest exhibit featuring extraordinary crystals and gems central to the cultures of southern Asia.

Showcases the diverse natural shapes of rough diamonds and explores how geological processes create their unique forms.

GIA’s Al Gilbertson receives the American Gem Society’s highest honor.