RocksdayManganite vs Psilomelane
The quickest way to tell Manganite from Psilomelane: Psilomelane is clearly harder: Mohs 5–6 versus 4.
Black manganese oxide-hydroxide in striated prisms. The streak is brown, not black.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
A group name for hard, black manganese oxides — including romanechite and hollandite — not a single mineral species.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
Quick tests
- Hardness: Psilomelane is clearly harder: Mohs 5–6 versus 4.
Key differences
- Psilomelane is botryoidal and harder, not prismatic.
Side by side
| Property | Manganite | Psilomelane |
|---|---|---|
| Type | Mineral | Mineraloid |
| Mohs hardness | 4 | 5–6 |
| Luster | Submetallic | Submetallic to dull |
| Streak | Brown | Brown |
| Colors | Black, Gray | Black, Gray |
| Crystal system / structure | Monoclinic | Botryoidal mixture of manganese oxides |
| Specific gravity | 4.3–4.4 | 3.7–4.7 |
| Formula | MnO(OH) | — |
| Found in | Ilfeld, Harz, Germany; Cornwall, England | Romanèche, France; Arizona |
Properties that are the same for both are grayed out.
How to identify manganite
- Black prisms with lengthwise striations.
- Reddish-brown to dark brown streak.
- Hardness 4 — a knife scratches it.
Crystal system: Monoclinic
Full Manganite guide →How to identify psilomelane
- Black, often grape-like (botryoidal) or massive.
- Brownish-black streak.
- Harder than pyrolusite: a knife may barely scratch it.
Structure: Botryoidal mixture of manganese oxides
Full Psilomelane guide →More comparisons
Frequently asked questions
What is the difference between manganite and psilomelane?
Manganite is a mineral with a Mohs hardness of 4 and a submetallic luster, usually black or gray. Psilomelane is a mineraloid with a Mohs hardness of 5–6 and a submetallic to dull luster, usually black or gray.
How can you tell manganite from psilomelane?
Psilomelane is clearly harder: Mohs 5–6 versus 4. Psilomelane is botryoidal and harder, not prismatic.
Could you tell them apart from a blurry close-up?
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