Stellerite
| Stellerite | |
|---|---|
| General | |
| Category | Tectosilicate minerals, zeolite group, stilbite subgroup |
| Formula | Ca(Al2Si7O18)·7H2O |
| IMA symbol | Ste |
| Strunz classification | 9.GE.15 |
| Crystal system | Orthorhombic |
| Crystal class | Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) |
| Space group | Fmmm |
| Identification | |
| Color | Colorless to white, pink, orange |
| Crystal habit | Spherical, Stellate, Tabular |
| Cleavage | Perfect on {010} |
| Fracture | Uneven |
| Mohs scale hardness | 4.5 |
| Luster | Pearly |
| Streak | white |
| Diaphaneity | Transparent to translucent |
| Specific gravity | approximately 2.2 |
| Density | 2.13 g/cm3 |
| Optical properties | Biaxial (-), a=1.4848, b=1.4864-1.4964, g=1.4979 |
| Birefringence | δ = 0.013 |
| References | |
Stellerite is a rare mineral discovered by and named after Georg Wilhelm Steller, a German explorer and zoologist. The mineral has a general formula of Ca[Al2Si7O18]·7H2O. Like most rare minerals, there are few commercial uses for stellerite. Mineral collectors are lucky to find it in good enough crystal form. Zeolites, including stellerite, have been studied using a dehydration process to gauge the potential use of their phases as molecular sieves, sorbents, and catalysts. Its occurrences are in cavities of andesite as sheaf-like clusters of small crystals.