Image: <bdi><a href="https://www.wikidata.org/wiki/Q56247090" class="extiw" title="d:Q56247090"><span title="mineral collector and dealer">Robert M. Lavinsky</span></a></bdi> (CC BY-SA 3.0)
orthorhombicrareOxides
Alexandrite
BeAl₂O₄
A faceted Alexandrite gemstone, known for its remarkable color-change effect, appearing green in daylight and reddish-purple under incandescent light. The image displays a vibrant green specimen.
Alexandrite Physical Properties
Mohs Hardness
8.5Crystal System
orthorhombicLuster
vitreousStreak Color
whiteCleavage
imperfect on {110}, distinct on {011}Fracture
conchoidal to unevenSpecific Gravity
3.75Colors
green, reddish-purple, yellowish-green, brownish-greenTransparency
transparentType Locality
Carnaiba Mine, Pindobaçu, Campo Formoso District, Bahia, Northeast Region, BrazilMineral Group
OxidesUses
jewelry, collectorAssociated Minerals
quartz, feldspar, mica, beryl, garnetRarity
rareGeological Context
Alexandrite forms in pegmatites, mica schists, and sometimes in alluvial deposits, requiring the presence of both beryllium and chromium for its unique composition and color-change properties.
