Tourmaline
| Colour | Black, Pink, Green, Clear, Brown, Red, Orange, Yellow, Blue, Purple |
|---|---|
| Mohs hardness | 7.0–7.5 |
| Lustre | Vitreous, sometimes resinous |
| Streak | White |
| Crystal system | Trigonal |
| Transparency | Translucent to opaque |
| Cleavage | Indistinct |
| Fracture | Uneven, small conchoidal |
| Specific gravity | 3.06+0.20–0.06 |
What is Tourmaline?
Tourmaline is a crystalline silicate mineral group in which boron is compounded with elements such as aluminium, iron, magnesium, sodium, lithium, or potassium. This gemstone comes in a wide variety of colors.
How to identify Tourmaline
- Lustre: Vitreous, sometimes resinous.
- Hardness: Mohs 7.0–7.5 — hard enough to scratch glass.
- Streak: White.
- Habit: Trigonal crystal system.
Tourmaline value
Tourmaline is a fine gemstone priced per carat by quality — colour, clarity, cut, carat and origin — not by weight in grams. Typical market ranges:
| Quality | Price per carat |
|---|---|
| Commercial | $20–$150 / ct |
| Good | $150–$1,500 / ct |
| Fine | $600–$10,000 / ct |
| Top | $10,000–$150,000+ / ct |
Ranges cross-validated across two independent research passes against gemstone price guides, 2026-06 — sources: gia.edu, onestepgems.com. Colour saturation, clarity, cut and origin move the price enormously, and treatments or lab-grown stones sell for a fraction — so this is a guide, not an appraisal. Have anything valuable checked by a certified gemmologist. See the full crystal & gemstone value guide.
