anhydriittina

Anhydriitti is the Swedish name for the mineral anhydrite. Anhydrite is a sulfate mineral composed of anhydrous calcium sulfate (CaSO4). It is a colorless, white, or gray mineral that can sometimes have blue or violet hues. Anhydrite is relatively soft, with a Mohs hardness of 3.5 to 4, and has a specific gravity of around 2.9 to 3.0. It occurs in a variety of geological environments, often found in evaporite deposits, where it forms from the evaporation of sulfate-rich brines. These deposits can be associated with salt lakes and seas. Anhydrite is also found in hydrothermal veins and as a gangue mineral in some ore deposits.

When anhydrite is exposed to water, it slowly hydrates to form gypsum (CaSO4·2H2O). This transformation is important in geological processes and can affect the stability of rocks. Anhydrite has various industrial uses. It is a raw material in the production of sulfuric acid, cement, and plaster of Paris. It can also be used as a drying agent due to its ability to absorb moisture. In some regions, anhydrite is mined for its decorative potential, although it is less commonly used than gypsum for artistic purposes. The mineral's name comes from the Greek words "an" meaning without and "hydor" meaning water, reflecting its anhydrous nature.