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ALEXANDRITE

Alexandrite

Alexandrite

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ALEXANDRITE

ALEXANDRITE Green in sunlight. Red in lamplight. Color-changing alexandrite is nature’s magic trick.

OVERVIEW

ABOUT ALEXANDRITE

Often described by gem aficionados as “emerald by day, ruby by night,” alexandrite is the very rare color-change variety of the mineral chrysoberyl. Originally discovered in Russia’s Ural Mountains in the 1830s, it’s now found in Sri Lanka, East Africa, and Brazil, but fine material is exceptionally rare and valuable.

BIRTHSTONES & ANNIVERSARIES

Alexandrite is a birthstone for June, along with pearl and moonstone. Alexandrite is also the gem for the 55th wedding anniversary.

1830

The year alexandrite was discovered in Russia’s Ural Mountains.


CZAR ALEXANDER II

Gem’s namesake who emancipated Russia’s serfs and was assassinated in 1881.

580NM

This absorption band allows alexandrite to shift from red to green when viewed under different light sources.

FACTS

Mineral: Chrysoberyl

Chemistry: BeAl2O4

Color: Bluish green in daylight, purplish red in incandescent light

Refractive Index: 1.746 to 1.755

Birefringence: 0.008 to 0.010

Specific Gravity: 3.73

Mohs Hardness: 8.5

WHY WE LOVE THIS GEMSTONE

1 COLOR CHANGE

Making alexandrite change color from green to red is the world’s most fun use of a penlight.

2 LIGHT SOURCE

This gem provides dramatic proof of how much the light source affects color in gems.

3 PHENOMENA

Alexandrite can show both color change and a cat’s-eye: two phenomena in one gem.

QUALITY FACTORS

COLOR

Fine alexandrite is green to bluish green in daylight and red to purplish red in incandescent light.

CLARITY

Good quality alexandrite has few inclusions. Rarely, needle-like inclusions create a cat’s-eye.

CUT

Alexandrite is most often available in mixed cuts. Its rarity means it is often cut to save weight.

CARAT WEIGHT

Most cut gems weigh less than one carat. Larger, higher-quality gems rise in price dramatically.

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