IMA mineral species
Kidwellite
NaFe³⁺₉₊ₓ(PO₄)₆(OH)₁₁·3H₂O (x ≈ 0.33)
Phosphate mineral.
Properties
⛏ Mohs hardness3
💅🪙🍶🔪💎
A copper coin scratches it.
⚖ Density3.34 g/cm³
Heavy
🔷 Monoclinic✏️ streak yellow
| Chemical formula | NaFe³⁺₉₊ₓ(PO₄)₆(OH)₁₁·3H₂O (x ≈ 0.33) |
|---|---|
| Elements | Na, Fe, P, O, H |
| Crystal system | Monoclinic |
| Mohs hardness | 3 |
| Density | 3.34 g/cm³ |
| Streak | yellow |
| Color | yellow, yellow-green, light green, greenish-white |
| Cleavage | {100} |
| IMA symbol | Kdw |
| Nickel–Strunz class | 8.DK.20 |
“—” means no reliable value in Wikidata yet. Check Mindat for full data.
🌍 Where it's found
Type locality (where it was first described): Fodderstack Mountain, United States
- 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
- Kidwellite on Mindat.org
- Wikipedia article
- Wikidata item Q3815105 (source of this page's data – you can correct it there)
IMA mineral species
3–4
Monoclinic
YellowGoldGreenWhite & Clear