RocksdayAndradite vs Demantoid
To tell Andradite from Demantoid: Demantoid is the bright green gem variety, often with horsetail inclusions.
Calcium iron garnet. Its green gem variety, demantoid, disperses light into colors more strongly than diamond.
Photo: Didier Descouens, CC BY-SA 4.0
Green andradite garnet with a diamond-like sparkle. It bends light into colors more strongly than diamond, but it is much softer.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
Key differences
- Demantoid is the bright green gem variety, often with horsetail inclusions.
- Demantoid is the green gem variety of andradite.
Side by side
| Property | Andradite | Demantoid |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 6.5–7 | 6.5–7 |
| Luster | Adamantine to vitreous | Adamantine |
| Streak | White | White |
| Colors | Green, Yellow, Brown, Black | Green, Yellow |
| Crystal system | Cubic | Cubic |
| Specific gravity | 3.8–3.9 | 3.8–3.9 |
| Formula | Ca₃Fe₂(SiO₄)₃ | Ca₃Fe₂(SiO₄)₃ |
| Found in | Ural Mountains, Russia; Namibia | Ural Mountains, Russia; Namibia |
Properties that are the same for both are grayed out.
How to identify andradite
- Very bright, almost diamond-like luster.
- Green, yellow, brown or black dodecahedral crystals.
- Hardness 6.5–7.
Crystal system: Cubic
Full Andradite guide →How to identify demantoid
- Bright green with strong fire.
- Hardness only 6.5–7 — a steel file can scratch it, unlike emerald.
- Ural stones often show curving 'horsetail' fibers inside.
Crystal system: Cubic
Full Demantoid guide →More comparisons
Frequently asked questions
What is the difference between andradite and demantoid?
Andradite is a mineral with a Mohs hardness of 6.5–7 and an adamantine to vitreous luster, usually green, yellow, brown or black. Demantoid is a mineral with a Mohs hardness of 6.5–7 and an adamantine luster, usually green or yellow.
How can you tell andradite from demantoid?
Demantoid is the bright green gem variety, often with horsetail inclusions. Demantoid is the green gem variety of andradite.
Could you tell them apart from a blurry close-up?
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