Investigates the correlations between peak positions in the 3309 cm–1 series with trace element concentrations for ruby, metamorphic and basalt-related blue sapphire, and laboratory-grown sapphire.

Archival research and gemological characterization reveal the geographic origin of two emeralds set in a pendant linked to Catherine de’ Medici, Queen of France from 1547 to 1559.

Presents the first scientific and historical study conducted on the 2.33 ct Winston Red, the fifth-largest known Fancy red diamond in existence.

A black opal cabochon set in a ring displays vivid orange play-of-color.

A summary of the findings at the 2025 Tucson gem shows.

Uniquely saturated examples of the collector stone were on display at GJX.

A look at the most popular phenomenal gems exhibited at the 2025 Tucson gem shows.

Photoluminescence spectroscopy examines how gemstones absorb and emit light, uncovering crucial details about their identity and color origin through the detection of microscopic defects and impurities.

Photoluminescence imaging, which analyzes how gemstones glow under ultraviolet light, is an important analytical tool for detecting impurities, natural versus synthetic gems, and treatments through the observation of fluorescence and phosphorescence patterns.

GIA’s laboratories use advanced instrumentation and research to deliver accurate grading, identification, and origin determination for natural and laboratory-grown diamonds, colored stones, and pearls.