Gypsum
What is Gypsum?
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO₄·2H₂O. It is the most common sulfate mineral. Gypsum is a non-metallic mineral that is typically white, colorless, or gray, but can also be found in various other colors due to impurities. It is known for its softness and can be easily scratched with a fingernail. Gypsum is used in a variety of applications, including the production of plaster of Paris, drywall, and cement. It is also used as a soil amendment and in the manufacturing of various industrial products.
Optical Properties
- Refractive Index
- 1.520-1.530
- Birefringence
- 0.009-0.020
- Pleochroism
- None
- Optical Character
- Biaxial (+)
- Dispersion
- Low
Gypsum Market Value Calculator
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Gypsum Localities Map
See where Gypsum is found with a localities map, collecting zones, and geology context. Generate a sample map preview below.
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Quick Facts
Physical Properties
- Color
- White, colorless, gray, yellow, red, brown, or black
- Hardness (Mohs)
- 2
- Density
- 2.32 - 2.33 g/cm³
- Streak
- White
Chemical Properties
- Chemical Formula
- CaSO₄·2H₂O
- Elements
- Calcium, Sulfur, Oxygen, Hydrogen
Also Known As
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