Carnelian
| Also known as | Chalcedony (Chalcedony family) |
|---|---|
| Colour | Orange, Red, Brown |
| Mohs hardness | 6.5–7.0 |
| Lustre | Waxy to resinous |
| Streak | White |
| Crystal system | Trigonal (quartz), monoclinic (moganite) |
| Transparency | Translucent to opaque |
| Cleavage | Absent |
| Fracture | Uneven, splintery, conchoidal |
| Chemical formula | SiO 2 (silicon dioxide) |
| Specific gravity | 2.58–2.64 |
What is Carnelian?
Carnelian is a brownish-red mineral commonly used as a semiprecious stone. Similar to carnelian is sard, which is generally harder and darker; the difference is not rigidly defined, and the two names are often used interchangeably. Both carnelian and sard are varieties of the silica mineral chalcedony colored by impurities of iron oxide. The color can vary greatly, ranging from pale orange to an intense almost-black coloration. Significant localities include Yanacodo, Peru and Ratnapura, Sri Lanka. It has been found in Indonesia, Brazil, India, Iran, Russia (Siberia), and Germany.
How to identify Carnelian
- Lustre: Waxy to resinous.
- Hardness: Mohs 6.5–7.0 — about as hard as a steel knife.
- Streak: White.
- Habit: Trigonal (quartz), monoclinic (moganite) crystal system.
Carnelian in different forms
Frequently asked questions
How hard is Carnelian?
Carnelian is Mohs 6.5–7.0 on the hardness scale.
What colour is Carnelian?
Carnelian is typically orange, red, brown (Reddish, orange, brownish).