RocksdayEclogite vs Skarn
How to tell them apart
A striking red-and-green rock of garnet and green pyroxene formed at great depth.
Photo: No machine-readable author provided. Woudloper assumed (based on copyright claims)., Public domain
Colorful rock formed where hot fluids from magma react with limestone, often rich in ores.
Photo: Dexter Perkins, CC0
Key differences
- Eclogite is uniform garnet and green pyroxene from great depth.
Side by side
| Property | Eclogite | Skarn |
|---|---|---|
| Type | Metamorphic rock | Metamorphic rock |
| Mohs hardness | 6–7 | 5–7 |
| Luster | Vitreous | Vitreous to granular |
| Colors | Green, Red | Green, Brown, Red, White |
| Crystal system / structure | Coarse, garnet and omphacite | Coarse calc-silicate |
| Specific gravity | 3.4–3.6 | 3–3.5 |
| Found in | Western Norway; Western Alps, Italy | Sweden; Hunan, China |
Properties that are the same for both are grayed out.
How to identify eclogite
- Red garnets in a green matrix.
- Exceptionally heavy.
- Glassy, coarse crystals.
Structure: Coarse, garnet and omphacite
Full Eclogite guide →How to identify skarn
- Mix of garnet, green pyroxene and calcite.
- Heavy, coarse and colorful.
- Found at granite–limestone contacts.
Structure: Coarse calc-silicate
Full Skarn guide →More comparisons
Could you tell them apart from a blurry close-up?
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