RocksdayAgate vs Carnelian
How to tell them apart
Banded chalcedony — quartz made of microscopic crystals — that fills cavities in volcanic rock layer by layer. Light passes through the bands when held up to the sun.
Photo: James St. John, CC BY 2.0
Translucent orange-red chalcedony colored by iron oxide.
Photo: Hyperdeath, CC BY-SA 4.0
Key differences
- Agate shows distinct banding; carnelian is mostly uniform.
Side by side
| Property | Agate | Carnelian |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 6.5–7 | 6.5–7 |
| Luster | Waxy to vitreous | Waxy to vitreous |
| Streak | White | White |
| Colors | Red, Orange, White, Gray, Brown, Blue | Orange, Red, Brown |
| Crystal system | Microcrystalline quartz (chalcedony) | Microcrystalline quartz (chalcedony) |
| Specific gravity | 2.58–2.64 | 2.58–2.64 |
| Formula | SiO₂ | SiO₂ |
| Found in | Lake Superior shores; Rio Grande do Sul, Brazil | India; Brazil |
Properties that are the same for both are grayed out.
How to identify agate
- Concentric or parallel bands, often in red, orange and white.
- Translucent at the edges when backlit.
- Waxy surface on rough, weathered pieces ('pitted' rind).
- Hard enough to scratch glass.
Crystal system: Microcrystalline quartz (chalcedony)
Full Agate guide →How to identify carnelian
- Glows orange-red when held up to light.
- Even color or soft cloudy banding.
- Waxy surface, hard enough to scratch glass.
Crystal system: Microcrystalline quartz (chalcedony)
Full Carnelian guide →More comparisons
Could you tell them apart from a blurry close-up?
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