| Alamosite | |
| Category: | Inosilicates |
| Formula: | Pb12Si12O36 |
| Imasymbol: | Aam[1] |
| Strunz: | 9.DO.20 |
| Dana: | 65.7.1.1 |
| System: | Monoclinic |
| Class: | Prismatic (2/m) (same H-M symbol) |
| Symmetry: | P2/c |
| Unit Cell: | a = 11.209, b = 7.041 c = 12.22 [Å]; β = 113.15°; Z = 12 |
| Color: | Colorless |
| Cleavage: | perfect |
| Mohs: | 4.5 |
| Luster: | Adamantine |
| Refractive: | nα = 1.947, nβ = 1.961, nγ = 1.968 |
| Opticalprop: | Biaxial (−) |
| Birefringence: | δ = 0.021 |
| 2V: | 65° (meas.) |
| Streak: | White |
| Gravity: | 6.49 |
| Diaphaneity: | Transparent to translucent |
| References: | [2] [3] |
Alamosite (Pb12Si12O36) is a colorless silicate mineral named after the place where it was discovered, Álamos, Sonora, Mexico. It is a rare secondary mineral occurring in the oxidized zones of lead-rich deposits. For example, the infobox picture shows its association with black leadhillite.[2]