Alexandrite is a rare variety of chrysoberyl prized for its remarkable color-change effect, appearing emerald-green in daylight and raspberry-red under incandescent light. It is commonly found as cyclic twins or tabular crystals within specific geological environments like mica schists. Collectors should look for a sharp, distinct shift in color and high clarity to distinguish it from imitations.
Is this alexandrite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch alexandrite with a known reference. Alexandrite sits at Mohs 8.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Alexandrite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Alexandrite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: emerald green, red, purplish-red, brownish.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: tabular crystals, often cyclic twins.
Often confused with
Alexandrite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside alexandrite
Minerals reported to co-occur with alexandrite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- BeAl₂O₄
- Mohs hardness
- 8.5
- Density
- 3.7-3.8 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Orthorhombic
- Crystal habit
- Tabular Crystals, Often Cyclic Twins
- Cleavage
- Distinct
- Rarity
- Rare
- Uses
- Gemstone, Collector
- Host rock
- Pegmatites and Mica Schists
- Typical price
- $2,000-20,000+ per carat depending on color change intensity and clarity
Where rockhounds find alexandrite
Classic worldwide localities
- Ural Mountains, Russia
- Minas Gerais, Brazil
- Sri Lanka
- Tanzania
- Zimbabwe
Field-hunting tip
Look in pegmatites and mica schists country, the host setting where alexandrite typically forms. If you start seeing phlogopite, emerald, phenakite in float, you are in the right ground. Field specimens usually show a tabular crystals, often cyclic twins habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify alexandrite?+
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How much is alexandrite worth?+
What rocks look like alexandrite?+
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Find alexandrite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
