Crystal & mineral guide
Zircon
ZrSiO₄
High-dispersion natural gem — not to be confused with cubic zirconia.
Identify Zircon with RockScan Get on the App StoreAbout Zircon
Natural zircon has high RI and dispersion that can approach diamond's fire. Blue zircon is typically heat-treated from brown. Distinct from synthetic CZ. High birefringence doubles facet junctions under loupe — a key field ID.
Zircon belongs in a crystal identifier workflow because photo cues — color zoning, crystal habit, and surface luster — combine with measurable traits like Mohs 6.5–7.5 and specific gravity 3.93–4.73. Use RockScan’s camera to get a first-pass ID, then confirm with the checklist below.
Zircon properties
| Mohs hardness | 6.5–7.5 |
|---|---|
| Crystal system | Tetragonal |
| Luster | Adamantine to vitreous |
| Color | Colorless, blue (treated), brown, red, green |
| Composition | Zirconium silicate |
| Formation | Igneous and metamorphic rocks; placer deposits |
| Occurrence | Cambodia, Sri Lanka, Australia, East Africa |
| Specific gravity | 3.93–4.73 |
| Cleavage | Imperfect |
How to identify Zircon
- Doubling of facet edges under loupe (DR)
- High SG; adamantine flash
- Not the same as cubic zirconia
Collector notes
- Some zircons are among Earth's oldest minerals (>4 Ga)
- Name unrelated to synthetic CZ despite market confusion
Value context: Bright blue heat-treated stones and fine natural browns/reds trade actively.
Zircon FAQ
How do you identify Zircon?
Zircon (ZrSiO₄) is typically recognized by colorless, blue (treated), brown, red, green color, adamantine to vitreous luster, Mohs hardness 6.5–7.5, and tetragonal crystal system. RockScan can suggest Zircon from a photo and surface these checks on the result card.
What is Zircon made of?
Zircon composition: Zirconium silicate. It forms via igneous and metamorphic rocks; placer deposits and is found in Cambodia, Sri Lanka, Australia, East Africa.
Is Zircon valuable?
Bright blue heat-treated stones and fine natural browns/reds trade actively.
