| Admontite | |
| Category: | Nesoborates |
| Formula: | MgB6O10·7H2O or MgB6O7(OH)6·4H2O |
| Imasymbol: | Amt[1] |
| Strunz: | 6.FA.15 |
| Dana: | 26.6.3.1 |
| System: | Monoclinic |
| Class: | Prismatic (2/m) (same H-M symbol) |
| Symmetry: | P21/c |
| Color: | colorless |
| Cleavage: | Absent |
| Fracture: | Conchoidal - Fractures developed in brittle materials characterized by smoothly curving surfaces, (e.g. quartz) |
| Mohs: | 2 - 3 - Gypsum-Calcite |
| Refractive: | nα = 1.442 nγ = 1.504 |
| Opticalprop: | Biaxial (−) |
| Birefringence: | δ = 0.062 |
| Dispersion: | None |
| Streak: | White |
| Density: | 1.82 - 1.87, Average = 1.84 |
| References: | [2] [3] [4] |
Admontite is a hydrated magnesium borate mineral with formula MgB6O10·7H2O.
Occurrence - In a gypsum deposit.Associations: gypsum, anhydrite, hexahydrite, löweite, eugsterite, pyrite, quartz.
It is named after Admont, Austria. Its Mohs scale rating is 2 to 3.