| Formula | MgAl2O4 |
| Molecular mass | 142.27 g/mol |
| admixture | Ti,Fe,Zn,Mn,Ca |
| IMA Status | Valid |
| Systematics according to IMA (Mills et al., 2009) | |
| Class | Oxides and hydroxides |
| Group | Aluminospinels |
| Physical properties | |
| Color | Colorless, red, pink, blue, green, purple, yellow |
| Dash color | grayish white |
| Shine | Glass |
| Transparency | Transparent to translucent |
| Mohs hardness | 7.5 – 8 |
| fragility | Fragile |
| Cleavage | imperfect |
| kink | conchoidal |
| Density | 3.57-3.72 g/cm³ |
| Crystallographic properties | |
| space group | Fd3m |
| Syngony | cubic |
| Twinning | |
| Optical properties | |
| optical type | isotropic |
| Refractive index | 1.71-1.76 |
| Birefringence | Missing |
| dichroism | |
| optical relief | High |
| Dispersion of optical axes | 0.026 |
| Pleochroism | Visible |
| Luminescence | From none to strong (under LW). In red – strong, red (LW, SW); blue has a weak reddish or green (LW, SW); green-weak reddish (LW) |
| Diffusion |
Strode Anna
Anna Strod – director of the jewelry online store Myjewels.ru Author and editor of the jewelry blog Myjewels.ru
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