RocksdayHiddenite vs Prasiolite
To tell Hiddenite from Prasiolite: Hiddenite is spodumene: it cleaves and is slightly softer.
Green spodumene. The original North Carolina stones are colored by chromium; pale green spodumene from elsewhere is often sold under the same name.
Photo: Parent Géry, CC BY-SA 3.0
Green quartz. Natural pieces are uncommon; nearly all prasiolite for sale is amethyst that has been heated, or yellow quartz that has been irradiated.
Photo: Mauro Cateb, CC BY-SA 4.0
Key differences
- Hiddenite is spodumene: it cleaves and is slightly softer.
Side by side
| Property | Hiddenite | Prasiolite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 6.5–7 | 7 |
| Luster | Vitreous | Vitreous |
| Streak | White | White |
| Colors | Green, Yellow | Green |
| Crystal system | Monoclinic | Trigonal |
| Specific gravity | 3.1–3.2 | 2.65 |
| Formula | LiAlSi₂O₆ | SiO₂ |
| Found in | Alexander County, North Carolina; Afghanistan | Lower Silesia, Poland; Bahia, Brazil |
Properties that are the same for both are grayed out.
How to identify hiddenite
- Yellow-green to emerald-green flattened prisms.
- Two cleavages nearly at right angles.
- Hardness about 6.5–7, so a knife blade does not scratch it.
Crystal system: Monoclinic
Full Hiddenite guide →How to identify prasiolite
- Even leek-green to olive, not banded like aventurine.
- Hardness 7, with quartz's curved fracture.
- Heated amethyst often keeps a geode shape with paler bases.
Crystal system: Trigonal
Full Prasiolite guide →More comparisons
Frequently asked questions
What is the difference between hiddenite and prasiolite?
Hiddenite is a mineral (LiAlSi₂O₆) with a Mohs hardness of 6.5–7 and a vitreous luster, usually green or yellow. Prasiolite is a mineral (SiO₂) with a Mohs hardness of 7 and a vitreous luster, usually green.
How can you tell hiddenite from prasiolite?
Hiddenite is spodumene: it cleaves and is slightly softer.
Could you tell them apart from a blurry close-up?
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