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Alexandrite
Green in sunlight. Red in lamplight. Color-changing alexandrite is nature’s magic trick.
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Tools
Research
The Geographic Origin Dilemma
An overview of the geographic origin complexities facing the gem and jewelry industry today.
Field Gemology: Building a Research Collection and Understanding the Development of Gem Deposits
With more than 90 field expeditions on six continents since 2008, GIA has accumulated over 22,000 colored stone reference samples. This extensive collection of colored stones with known origins supports GIA’s research on geographic origin determination.
Geographic Origin Determination of Alexandrite
The geographic source of this rare color-change gem has a significant impact on value. Trace element chemistry profiles allow GIA to accurately determine origin for alexandrite from several countries.
Guardians of Trust: GIA’s Innovative Research, Instruments and Services
GIA’s services and instruments have grown in importance and impact as new gem treatments and laboratory-grown gems enter the market.
Pleochroism and Color Change in Faceted Alexandrite: Influence of Cut and Sample Orientation
Shows how alexandrite’s color and color change are affected by cut and the orientation of table facets.
Cat’s-Eye Alexandrite with Unique Inclusion Pattern
Examination of a chatoyant alexandrite cabochon.
Record-Size Natural Moissanite Crystals Discovered in Israel
Natural moissanite crystals found in Israel have broken world records, with evidence of larger crystals in the area.
Chrysoberyl and Alexandrite from the Pegmatite Districts of Minas Gerais, Brazil
Mining fine cat's-eye chrysoberyl and alexandrite in Brazil.
Gemstones with Alexandrite Effect
The term "alexandrite effect" refers to the apparent change of color in certain minerals from blue-green or greenish violet in daylight to red or reddish violet in incandescent light.
