IMA mineral species
Guilleminite
Ba(UO₂)₃(Se⁴⁺O₃)₂O₂·3H₂O
Uranyl selenite mineral.
Properties
⛏ Mohs hardness2
💅🪙🍶🔪💎
Scratches with a fingernail.
| Chemical formula | Ba(UO₂)₃(Se⁴⁺O₃)₂O₂·3H₂O |
|---|---|
| Elements | Ba, U, O, Se, H |
| Crystal system | Orthorhombic |
| Mohs hardness | 2 |
| Density | — |
| Streak | — |
| Color | — |
| IMA symbol | Gul |
| Nickel–Strunz class | 4.JJ.10 |
“—” means no reliable value in Wikidata yet. Check Mindat for full data.
Care & Handling
- 🪶 Soft, Scratches Easily Mohs 2: 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): Musonoi mine, Democratic Republic of the Congo
- 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
- Guilleminite on Mindat.org
- Wikipedia article
- Wikidata item Q3120528 (source of this page's data – you can correct it there)
IMA mineral species
2–3
Orthorhombic
YellowGreen
Soft, Scratches Easily