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Post: chalk

Gypsum is a soft sulfate mineral that consists of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is widely mined and used as a fertilizer and as the main ingredient in many forms of plaster, blackboard/sidewalk plaster and drywall. A type of fine-grained white or colored plaster, called alabaster, was used for sculpture by many cultures, including ancient Egypt, Mesopotamia, ancient Rome, the Byzantine Empire, and the Nottingham alabasters of medieval England. Gypsum also crystallizes as semi-transparent selenite crystals. It is formed as an evaporite mineral and as a product of anhydrite hydration.

The Mohs mineral hardness scale defines gypsum as a hardness value of 2 based on scratch hardness comparison.

Commercial quantities of gypsum are found in the cities of Araripina and Grajaú in Brazil. in Pakistan, Jamaica, Iran (the second largest producer in the world), Thailand, Spain (the main producer in Europe), Germany, Italy, England, Ireland and Canada and the United States of America. Large open pit mines are located in many places including Fort Dodge, Iowa, which sits on one of the largest gypsum deposits in the world, and Gypsum City, California, United States, and East Kuta, Kalimantan, Indonesia. There are also several small mines in places like Kalannie in Western Australia, where gypsum is sold to private buyers to add calcium and sulfur as well as reduce aluminum toxicity in the soil for agricultural purposes.

11 m (36 ft) long gypsum crystals have been found in the caves of the Naica mine in Chihuahua, Mexico. The crystals grew in the extremely rare and stable natural environment of the cave. The temperature remained at 58 °C (136 °F) and the cave was filled with mineral-rich water that allowed the crystals to grow. The largest of those crystals weighs 55 tons (61 short tons) and is about 500,000 years old.

If you intend to extract this soft sulfate mineral, we are always with you in the extraction machinery section from the beginning to the start of the factory.

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