Image: <bdi><a href="https://www.wikidata.org/wiki/Q126871365" class="extiw" title="d:Q126871365"><span title="photographer from the United States">Shannon Heinle</span></a></bdi> (CC0)
orthorhombicrareOxides
Alexandrite
BeAl2O4
A rare and valuable gemstone variety of chrysoberyl, renowned for its dramatic color change from green or bluish-green in daylight to red or purplish-red under incandescent light.
Alexandrite Physical Properties
Mohs Hardness
8.5Crystal System
orthorhombicLuster
vitreousStreak Color
whiteCleavage
distinct on {110}, poor on {010} and {100}Fracture
conchoidal to unevenSpecific Gravity
3.75Colors
green, bluish-green, red, purplish-redTransparency
transparentType Locality
Ural Mountains (Russia), Brazil, Sri Lanka, Tanzania, IndiaMineral Group
OxidesUses
jewelry, collectorAssociated Minerals
quartz, feldspar, mica, beryl, tourmaline, garnetRarity
rareGeological Context
Forms in granitic pegmatites, mica schists, and occasionally in contact metamorphic deposits. It can also be found in placer deposits due to its hardness and resistance to weathering.
