APPLICATIONS: | Used in some cements, a source of sulfate for sulfuric acid. |
ASSOCIATED MINERALS: | Calcite, halite, and occasionally sulfides such as galena and pyrite. |
CHEMICAL STRUCTURE: | CaSO4, Calcium Sulfate. |
CLASS: | Sulfates. |
CLEAVAGE: | Three directions forming rectangles, but perfect in one, very good in another and only marginally good in the third direction. |
COLOR: | Typically white, gray or colorless but also blue to violet. |
CRYSTAL HABITS: | Tabular, rectangular box formed by three pinacoids, often elongated in one direction forming a prismatic crystal. Most commonly massive and granular. |
CRYSTAL SYSTEM: | Orthorhombic, 2/m 2/m 2/m. |
FIELD INDICATORS: | Crystal habit, rectangular and non-uniform cleavage and low density. |
FRACTURE: | Conchoidal. |
GENERAL INFORMATION: | Some specimens are fluorescent under UV light. |
GEOGRAPHY: | Mexico; Peru; Germany and New Mexico. |
HARDNESS: | 3.5. |
LUSTER: | Vitreous. |
TRANSPARENCY: | Transparent to translucent. |
SPECIFIC GRAVITY: | 3.0. |
STREAK: | White. |
