RocksdayAnthracite vs Coal
How to tell them apart
The highest-grade coal: hard, shiny and almost pure carbon.
Photo: Jakec, CC BY-SA 4.0
A rock formed from buried, compressed plant material — ancient swamp forests turned to stone.
Photo: Amcyrus2012, CC BY 4.0
Key differences
- Bituminous coal is duller and leaves black dust.
Side by side
| Property | Anthracite | Coal |
|---|---|---|
| Type | Metamorphic rock | Sedimentary rock |
| Mohs hardness | 2.75–3 | 2–3 |
| Luster | Submetallic | Dull to submetallic |
| Colors | Black | Black, Brown |
| Crystal system / structure | Dense carbon, conchoidal fracture | Organic, layered |
| Specific gravity | 1.3–1.4 | 1.1–1.8 |
| Found in | Northeastern Pennsylvania; South Wales | Powder River Basin, Wyoming; Appalachia |
Properties that are the same for both are grayed out.
How to identify anthracite
- Shiny, nearly metallic black.
- Breaks with curved, glassy fractures.
- Barely dirties your fingers.
Structure: Dense carbon, conchoidal fracture
Full Anthracite guide →How to identify coal
- Black and very light for a rock.
- Leaves black dust on hands.
- Layered, with blocky or curved breaks.
- Burns.
Structure: Organic, layered
Full Coal guide →More comparisons
Could you tell them apart from a blurry close-up?
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