Sexually transmitted diseases (STDs) remain a major public health challenge in the U.S., especially among women, who. disproportionately bear the long-term consequences of STDs. For example, each year untreated STDs cause infertility in.
Chemically known as âcalcium sulfate dihydrate,â gypsum contains calcium, sulfur bound to oxygen, and water. Gypsum is an abundant mineral and takes forms including alabasterâa material used in decoration and construction as far back as ancient Egypt.hemically known as âcalcium sulfate dihydrate,â gypsum contains calcium, sulfur bound to oxygen, and water. Gypsum is an abundant mineral and takes forms including alabasterâa material used in decoration and construction as far back as ancient Egypt.
Gypsum crystals in the Cave of the Crystals in Mexico. Note person for scale. Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO 4 Â·2H 2 O. It can be used as a fertilizer, is the main constituent in many forms of plaster and in blackboard chalk, and is widely mined.n arid areas, gypsum can occur in a flower-like form, typically opaque, with embedded sand grains called desert rose. It also forms some of the largest crystals found in nature, up to 12 metres (39 ft) long, in the form of selenite.