RocksdayGarnet vs Ruby
How to tell them apart
A family of silicate minerals that grow as round, many-faced crystals. Deep red almandine studding schist is the classic find.
Photo: Moha112100, CC BY-SA 3.0
Red corundum, colored by chromium. After diamond it's the hardest natural gemstone.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
Quick tests
- Hardness: Ruby is clearly harder: Mohs 9 versus 7–7.5.
Key differences
- Garnet is softer and forms rounded crystals.
Side by side
| Property | Garnet | Ruby |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 7–7.5 | 9 |
| Luster | Vitreous | Adamantine to vitreous |
| Streak | White | White |
| Colors | Red, Brown | Red, Pink |
| Crystal system | Cubic | Trigonal |
| Specific gravity | 3.9–4.3 | 3.97–4.05 |
| Formula | Fe₃Al₂(SiO₄)₃ (almandine) | Al₂O₃ (with chromium) |
| Found in | Gore Mountain, New York; Emerald Creek, Idaho | Mogok, Myanmar; Montepuez, Mozambique |
Properties that are the same for both are grayed out.
How to identify garnet
- Ball-shaped crystals with 12 or 24 faces.
- Deep wine-red to brown.
- Scratches glass.
- Often embedded in mica schist.
Crystal system: Cubic
Full Garnet guide →How to identify ruby
- Red to pinkish red, often in six-sided barrel crystals.
- Hardness 9 — scratches topaz and quartz.
- Glows red under a UV light.
Crystal system: Trigonal
Full Ruby guide →More comparisons
Could you tell them apart from a blurry close-up?
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