RocksdayDanburite vs Topaz
How to tell them apart
A clear calcium borosilicate whose crystals end in a chisel-like wedge.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
A fluorine-bearing silicate and the Mohs reference for hardness 8. Crystals are often clear with sharp, diamond-shaped cross-sections.
Photo: Parent Géry, CC BY-SA 3.0
Key differences
- Topaz has a perfect cleavage across the crystal.
Side by side
| Property | Danburite | Topaz |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 7–7.5 | 8 |
| Luster | Vitreous to greasy | Vitreous |
| Streak | White | White |
| Colors | Clear, White, Pink, Yellow | Clear, Yellow, Orange, Blue, Pink |
| Crystal system | Orthorhombic | Orthorhombic |
| Specific gravity | 2.97–3.03 | 3.49–3.57 |
| Formula | CaB₂(SiO₄)₂ | Al₂SiO₄(F,OH)₂ |
| Found in | Charcas, Mexico; Madagascar | Ouro Preto, Brazil; Topaz Mountain, Utah |
Properties that are the same for both are grayed out.
How to identify danburite
- Clear prisms with wedge-shaped tips.
- Hardness about 7.
- No good cleavage.
Crystal system: Orthorhombic
Full Danburite guide →How to identify topaz
- Harder than quartz (8).
- One perfect cleavage across the crystal — flat, mirror-like breaks.
- Feels heavier than quartz of the same size.
- Prisms with lengthwise striations.
Crystal system: Orthorhombic
Full Topaz guide →More comparisons
Could you tell them apart from a blurry close-up?
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