Gypsum
| Formula | CaSO4 • 2H2O |
| Origin | Swan Hill, Victoria (Australia) |
| Description | Spear-shaped brown-orange gypsum crystal |
| Classification (Lapis) | Sulfates |
| Crystal System | monoclinic |
| Hardness | 1,5 – 2,0 |
| Colour | colorless, white; if colored by impurities, yellow, tan, blue, pink, brown, reddish brown, gray, black |
| Streak | white |
| Luminescence | yellowish to partly orange |
| Luster | vitreous |
| Transparency (Opacity) | transparent to translucent |
| Cleavage | perfect |
| Fracture | splintery |
| Magnetism | negative |
| Geological Setting | a common constituent of sedimentary rocks, particularly marine salt deposits |
| Specific Gravity | 2,31 g/cm3 |
Kristallmodelle
#© Mark Holtkamp
