RocksdaySoapstone vs Talc
How to tell them apart
A soft metamorphic rock made mostly of talc. Easy to carve and excellent at holding heat.
Photo: Ra'ike (see also: de:Benutzer:Ra'ike), CC BY-SA 3.0
The softest mineral, number 1 on the Mohs scale. It feels soapy or greasy and leaves powder on your fingers.
Photo: Unknown, Public domain
Quick tests
- Texture: Soapstone is a rock — a mix of grains or minerals; Talc is a single mineral.
Key differences
- Pure talc is flakier and pearly.
- Soapstone is a rock made mostly of talc — massive and carvable rather than flaky.
Side by side
| Property | Soapstone | Talc |
|---|---|---|
| Type | Metamorphic rock | Mineral |
| Mohs hardness | 1–2.5 | 1 |
| Luster | Greasy | Pearly to greasy |
| Streak | — | White |
| Colors | Gray, Green, White | White, Green, Gray |
| Crystal system / structure | Massive, fine-grained | Monoclinic |
| Specific gravity | 2.7–2.8 | 2.7–2.8 |
| Formula | — | Mg₃Si₄O₁₀(OH)₂ |
| Found in | Minas Gerais, Brazil; Virginia | Vermont; Montana |
Properties that are the same for both are grayed out.
How to identify soapstone
- Feels soapy or greasy.
- A fingernail scratches it.
- Gray to green, uniform.
- Massive, not flaky.
Structure: Massive, fine-grained
Full Soapstone guide →How to identify talc
- Easily scratched by a fingernail.
- Slippery, soapy feel.
- Pearly sheen on flaky surfaces.
- Flakes don't spring back when bent.
Crystal system: Monoclinic
Full Talc guide →More comparisons
Could you tell them apart from a blurry close-up?
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