IMA mineral species
Cronstedtite
Fe²⁺₂Fe³⁺((Si,Fe³⁺)₂O₅)(OH)₄
Phyllosilicate mineral; polytypes: 1M, 1T, 2H2, 3T, 6R2, 6T2.
Properties
⛏ Mohs hardness3.5
💅🪙🍶🔪💎
A copper coin scratches it.
| Chemical formula | Fe²⁺₂Fe³⁺((Si,Fe³⁺)₂O₅)(OH)₄ |
|---|---|
| Elements | Fe, Si, O, H |
| Crystal system | — |
| Mohs hardness | 3.5 |
| Density | — |
| Streak | — |
| Color | — |
| IMA symbol | Cro |
| Nickel–Strunz class | 9.ED.15 |
“—” means no reliable value in Wikidata yet. Check Mindat for full data.
Care & Handling
- 🪶 Soft, Scratches Easily Mohs 3.5: softer than a steel knife, so it scratches easily. Store it apart from harder stones.
🌍 Where it's found
Type locality (where it was first described): Příbram District, Czech Republic
- Type locality
- Notable source / deposit
- Country of origin
Marker positions are approximate (region or locality level). Type localities from Wikidata; notable sources curated by Crystopedia.
Learn more
- Cronstedtite on Mindat.org
- Wikipedia article
- Wikidata item Q2706053 (source of this page's data – you can correct it there)
IMA mineral species
3–4
GreenBrownBlack
Soft, Scratches Easily