| Fontarnauite | |
|---|---|
 Fontarnauite, Anatolia, West Turkey | |
| General | |
| Category | Borate minerals |
| Formula (repeating unit) | (Na,K)2(Sr,Ca)(SO4)[B5O8(OH)]·2H2O |
| IMA symbol | Fon[1] |
| Strunz classification | 6.DA.60 |
| Crystal system | Monoclinic |
| Crystal class | Prismatic (2/m) (same H-M symbol) |
| Space group | P21/c |
| Identification | |
| Color | Light brown |
| Cleavage | Perfect {010} |
| Mohs scale hardness | 2.5 - 3 |
| References | [2][3] |
Fontarnauite is a relatively recently described, rare sulfate, borate mineral with the chemical formula (Na,K)2(Sr,Ca)(SO4)[B5O8(OH)]·2H2O. It is found in an evaporite boron deposit. It coexists with other evaporite boron minerals, especially probertite. It is monoclinic, crystallizing in the space group P21/c.[4][2]
It was named for Ramon Fontarnau i Griera, a materials scientist of the University of Barcelona.[2]