RocksdayBenitoite vs Sapphire
How to tell them apart
A rare blue barium titanium silicate with distinctive triangular crystals.
Photo: Didier Descouens, CC BY-SA 4.0
Gem corundum of any color except red. Blue sapphire gets its color from iron and titanium.
Photo: James St. John, CC BY 2.0
Quick tests
- Hardness: Sapphire is clearly harder: Mohs 9 versus 6–6.5.
Key differences
- Sapphire is far harder and doesn't fluoresce blue.
Side by side
| Property | Benitoite | Sapphire |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 6–6.5 | 9 |
| Luster | Vitreous | Adamantine to vitreous |
| Streak | White | White |
| Colors | Blue, White | Blue, Yellow, Pink, Orange |
| Crystal system | Hexagonal | Trigonal |
| Specific gravity | 3.6–3.7 | 3.95–4.03 |
| Formula | BaTiSi₃O₉ | Al₂O₃ |
| Found in | San Benito County, California | Sri Lanka; Madagascar |
Properties that are the same for both are grayed out.
How to identify benitoite
- Sapphire-blue triangular crystals.
- Glows brilliant blue under shortwave UV light.
- Usually on white natrolite.
Crystal system: Hexagonal
Full Benitoite guide →How to identify sapphire
- Hardness 9 — only diamond scratches it.
- Barrel or tapered six-sided crystals.
- Heavy for its size.
Crystal system: Trigonal
Full Sapphire guide →More comparisons
Could you tell them apart from a blurry close-up?
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