IMA mineral species
Holtstamite
Ca₃(Al,Mn³⁺)₂(SiO₄)₂(OH)₄
Mineral, nesosilicate garnet.
Properties
⛏ Mohs hardness6
💅🪙🍶🔪💎
Scratches glass; quartz scratches it.
| Chemical formula | Ca₃(Al,Mn³⁺)₂(SiO₄)₂(OH)₄ |
|---|---|
| Elements | Ca, Al, Mn, Si, O, H |
| Crystal system | Tetragonal |
| Mohs hardness | 6 |
| Density | — |
| Streak | — |
| Color | — |
| IMA symbol | Hts |
| Nickel–Strunz class | 9.AD.25 |
“—” means no reliable value in Wikidata yet. Check Mindat for full data.
🌍 Where it's found
Type locality (where it was first described): Wessels mine, South Africa
- 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
- Holtstamite on Mindat.org
- Wikidata item Q3786370 (source of this page's data – you can correct it there)
IMA mineral species
6–7
Tetragonal