IMA mineral species
Olmsteadite
KFe²⁺₂(Nb₅+,Ta₅+)(PO₄)₂O₂ * 2H₂O
Phosphate mineral.
Properties
⛏ Mohs hardness4
💅🪙🍶🔪💎
A steel knife scratches it, it won't scratch glass.
| Chemical formula | KFe²⁺₂(Nb₅+,Ta₅+)(PO₄)₂O₂ * 2H₂O |
|---|---|
| Elements | K, Fe, Nb, Ta, P, O, H |
| Crystal system | — |
| Mohs hardness | 4 |
| Density | — |
| Streak | — |
| Color | — |
| IMA symbol | Osd |
| Nickel–Strunz class | 8.DJ.05 |
“—” means no reliable value in Wikidata yet. Check Mindat for full data.
Care & Handling
- 🪶 Soft, Scratches Easily Mohs 4: softer than a steel knife, so it scratches easily. Store it apart from harder stones.
Learn more
- Olmsteadite on Mindat.org
- Wikidata item Q1284099 (source of this page's data – you can correct it there)
IMA mineral species
4–5
Soft, Scratches Easily