RocksdayCannel Coal vs Oil Shale
The quickest way to tell Cannel Coal from Oil Shale: Oil Shale feels noticeably heavier for its size (specific gravity 1.6–2.4 vs 1.1–1.4).
A fine, even bituminous coal that breaks with a curved fracture and burns with a bright flame.
Photo: Wilson44691, Public domain
Fine-grained rock rich in kerogen, an organic material that yields oil when heated.
Photo: Mike Davis, CC0
Quick tests
- Heft: Oil Shale feels noticeably heavier for its size (specific gravity 1.6–2.4 vs 1.1–1.4).
Key differences
- Oil shale is heavier and usually gray-brown and layered.
Side by side
| Property | Cannel Coal | Oil Shale |
|---|---|---|
| Type | Sedimentary rock | Sedimentary rock |
| Mohs hardness | 2–3 | 2–3 |
| Luster | Dull to greasy | Dull to waxy |
| Colors | Black, Gray | Brown, Black, Gray |
| Crystal system / structure | Fine-grained bituminous coal | Fine layered, organic-rich |
| Specific gravity | 1.1–1.4 | 1.6–2.4 |
| Found in | Scotland; Kentucky | Green River Formation, Colorado–Utah–Wyoming; Estonia |
Properties that are the same for both are grayed out.
How to identify cannel coal
- Black, dull to satiny, with a smooth curved break.
- Very light. Does not soil your hands as much as ordinary coal.
- A knife scratches it.
Structure: Fine-grained bituminous coal
Full Cannel Coal guide →How to identify oil shale
- Brown to black, fine layers.
- Light for a rock.
- Burns or smells of oil when heated.
Structure: Fine layered, organic-rich
Full Oil Shale guide →More comparisons
Frequently asked questions
What is the difference between cannel coal and oil shale?
Cannel Coal is a sedimentary rock with a Mohs hardness of about 2–3 and a dull to greasy luster, usually black or gray. Oil Shale is a sedimentary rock with a Mohs hardness of about 2–3 and a dull to waxy luster, usually brown, black or gray.
How can you tell cannel coal from oil shale?
Oil Shale feels noticeably heavier for its size (specific gravity 1.6–2.4 vs 1.1–1.4). Oil shale is heavier and usually gray-brown and layered.
Could you tell them apart from a blurry close-up?
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