Judging quality
Judge the completeness of the change, not just its presence. Lab-grown alexandrite and color-change synthetic sapphire are both common; the sapphire simulant shifts blue-to-violet rather than green-to-red.
Oxide
Alexandrite
Color-change chrysoberyl: green in daylight, raspberry red under incandescent light, caused by chromium sitting in a narrow transmission window. Fine natural material above a carat is one of the most expensive colored stones on earth.
Care
Hard and stable. Any cleaning method is safe.
History & lore
Named for Tsar Alexander II, whose birthday coincided with the 1830s Ural discovery — the red and green matched the Imperial military colors.
Cultural history, recorded as tradition rather than as medical or scientific claim.
Common questions about Alexandrite
- What is Alexandrite?
- Color-change chrysoberyl: green in daylight, raspberry red under incandescent light, caused by chromium sitting in a narrow transmission window. Fine natural material above a carat is one of the most expensive colored stones on earth.
- How hard is Alexandrite and what is it made of?
- Alexandrite is a Oxide-family mineral with the composition BeAl2O4 (Cr-bearing). It crystallizes in the orthorhombic system and rates 8.5 on the Mohs hardness scale. It occurs in emerald green, red, purple.
- Where does Alexandrite come from?
- Notable localities for Alexandrite include Ural Mountains, Russia, Brazil (Hematita), Sri Lanka, Tanzania.
- How do you tell good Alexandrite from filler?
- Judge the completeness of the change, not just its presence. Lab-grown alexandrite and color-change synthetic sapphire are both common; the sapphire simulant shifts blue-to-violet rather than green-to-red.
- How do you care for Alexandrite?
- Hard and stable. Any cleaning method is safe.
See it in person
Photographs only go so far
Both rooms are open six days a week, and there is always someone happy to pull pieces out of the case so you can compare them under the light.