Unusual Gemstones

Alexandrite

Current Market Range

$2,000 - $15,000+

Famous for dramatic color change; discovered in Russia in the 1830s.

Russia, Sri Lanka, Brazil, East Africa

Green in daylight, red in incandescent light

Chemical Formula

MgAl₂O₄ (Magnesium Aluminum Oxide)

Hardness

8.5

Luster

Vitreous (Glassy)

Crystal System

Orthorhombic

Refractive Index

1.75

Specific Gravity

3.68

Crystal System

Gemstones and minerals are classified into seven primary crystal systems based on their atomic structure.

Refractive Index

The refractive index (RI) of a material measure how much light is bent, or refracted, when entering the material from another medium.

Specific Gravity

The specific gravity (SG) of a substance is a measure of its density compared to water.

Chemical Formula

A chemical formula shows the types and quantities of atoms in a molecule.