What is gypsum and what is it made of?
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate. It rates a hardness value of 2 on the Mohs scale and is widely mined for fertilizer and for plaster, drywall, and chalk.
Questions about Gypsum
Short answers, pulled from the story.
Why is gypsum called plaster of Paris?
Gypsum became known as plaster of Paris because quarries in the Montmartre district of Paris long supplied burnt, calcined gypsum. The word gypsum itself comes from the Greek gypsos, meaning plaster.
What was the Plaster War of 1820?
The Plaster War of 1820 grew from a lively smuggling trade in Nova Scotia gypsum. American farmers were so eager to use gypsum as a fertilizer for wheat that they smuggled it across the border.
Where are the largest gypsum crystals found?
The largest gypsum crystals were found in the Naica Mine of Chihuahua, Mexico, reaching up to eleven metres long. The biggest weighs 55 tonnes and is around 500,000 years old, having grown in water-filled caves held at 58 degrees Celsius.
Where is White Sands National Park and why is it made of gypsum?
White Sands National Park lies in the US state of New Mexico and holds a 710 square kilometre expanse of white gypsum sand. President Herbert Hoover declared the gypsum dunes a protected national monument in 1933.
What is gypsum used for?
Gypsum is used in drywall, plaster, and Portland cement, as a fertilizer supplying calcium and sulfur, and as a tofu coagulant and dough conditioner. It also serves in surgical splints, dental impression plasters, sculpture as alabaster, and removing pollutants such as lead or arsenic from water.
Which country produces the most gypsum?
China is the largest gypsum producer, with an estimated 132,000 thousand metric tons in 2015. Iran is the world's second largest producer.