RocksdayHeliodor vs Topaz
To tell Heliodor from Topaz: Topaz is heavier and has one perfect cleavage.
Yellow to golden beryl, colored by iron. It grows as the same six-sided columns as emerald and aquamarine.
Photo: Parent Géry, 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 is heavier and has one perfect cleavage.
Side by side
| Property | Heliodor | Topaz |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 7.5–8 | 8 |
| Luster | Vitreous | Vitreous |
| Streak | White | White |
| Colors | Yellow, Gold | Clear, Yellow, Orange, Blue, Pink |
| Crystal system | Hexagonal | Orthorhombic |
| Specific gravity | 2.7–2.9 | 3.49–3.57 |
| Formula | Be₃Al₂Si₆O₁₈ | Al₂SiO₄(F,OH)₂ |
| Found in | Volodarsk, Ukraine; Minas Gerais, Brazil | Ouro Preto, Brazil; Topaz Mountain, Utah |
Properties that are the same for both are grayed out.
How to identify heliodor
- Yellow hexagonal prisms with flat ends.
- Hardness 7.5–8 — scratches quartz.
- Lighter in the hand than a yellow sapphire or a garnet.
Crystal system: Hexagonal
Full Heliodor 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
Frequently asked questions
What is the difference between heliodor and topaz?
Heliodor is a mineral (Be₃Al₂Si₆O₁₈) with a Mohs hardness of 7.5–8 and a vitreous luster, usually yellow or golden. Topaz is a mineral with a Mohs hardness of 8 and a vitreous luster, usually colorless, yellow, orange, blue or pink.
How can you tell heliodor from topaz?
Topaz is heavier and has one perfect cleavage.
Could you tell them apart from a blurry close-up?
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