Zircon
| Property | Details |
|---|
| Mineral | Zircon (zirconium silicate) |
| Mohs Hardness | 6 – 7.5 |
| Refractive Index | 1.810 – 2.024 (very high) |
| Birthstone | December (alternative) |
| Major Sources | Cambodia, Myanmar, Sri Lanka, Tanzania |
| Treatments | Heat treatment for blue and colorless (standard) |
Overview
Zircon (not to be confused with synthetic cubic zirconia) is a natural gemstone that has been used in jewelry for centuries. It possesses an exceptionally high refractive index that gives it outstanding brilliance and fire—in some colors, it can rival diamond for sparkle.
Why Zircon Is Special
Zircon has a uniquely high refractive index and a distinctive optical property called birefringence—you can see a doubling of the back facets when looking through the stone, giving it a characteristic soft, slightly fuzzy brilliance that experienced gem lovers find charming. Blue zircon was hugely fashionable in the Victorian and Art Deco eras. Colorless zircon has brilliance and fire that approaches diamond.
Colors & Varieties
Blue zircon: The most popular color, ranging from sky blue to vivid blue. Colorless zircon: Outstanding brilliance, historically used as a diamond simulant. Yellow-orange zircon: Warm, autumnal tones. Red and brown zircon: Natural colors before heat treatment. Green zircon: Rare and collectible. Blue and colorless zircon are produced by heat-treating reddish-brown crystals from Cambodia and Myanmar.
Care & Cleaning
Zircon ranges from 6 to 7.5 on the Mohs scale and can be brittle, with facet edges prone to chipping. Set zircon in protective mountings and avoid hard impacts. Clean with warm soapy water only. Avoid ultrasonic cleaners.