Gypsum
UNB-2017-0210Minerals » Sulphates
Description
Sample of several large, yellow euhedral arrowhead Gypsum crystals. Vitreous lustre. These large crystals are embedded on yellow, fibrous Gypsum crystals. Largest crystal size: 3.3 cm x 3.2 cm x 1.2 cm.
Gypsum (CaSO4 x 2H2O) can be white, colourless, grey, yellow, red or brown in colour. Lustre is vitreous or pearly on the cleavage. Streak is white and hardness is 1 1/2 to 2. Cleavage is perfect in one direction and distinct in two other directions. Gypsum usually occurs as untwinned single crystals that show rhombic form but can also be twinned arrowhead with beveled edges, granular, massive, fibrous (Satin Spar) or earthy in form.
Specifications
| Object name | Gypsum |
|---|---|
| ID | UNB-2017-0210 |
| Legal status | Permanent collection |
| Category | Mineral |
| Classification | Mineral group: Sulphates |
| Origin | Winnipeg, Manitoba, Canada |
| Pieces | 1 |
| Partial | No |
| Measurements |
|
Map of Origin
Publications
- Chesterman, C.W. 1979. Audubon Society, Field Guide to North American Rocks and Minerals. Knopf.