Sapphirine is a mineral , magnesium aluminum silicate from the class of silicates, which gave the name to the group and the supergroup of minerals. The chemical formula is Mg4 (Mg3Al9) O4 [Si3Al9O36]. The crystal structure is chain. Monoclinic syngony. The origin is metamorphic. It occurs in the form of aggregates of imperfectly formed crystals, forms granular masses, individual grains of irregular shape.
| Sapphirin | |
|---|---|
 Sapphirine Crystal. Madagascar | |
| Formula | Mg 4 (Mg 3 A 19 ) O 4 [Si 3 Al 9 O 36 ] |
| Impurity | Fe |
| Physical properties | |
| Color | light blue, blue gray, greenish gray |
| Trait color | White |
| Shine | Glass |
| Transparency | Transparent, translucent |
| Hardness | 7.5 |
| Cleavage | very imperfect |
| Kink | uneven |
| Density | 3.4 - 3.5 g / cm³ |
| Syngonia | Monoclinic |