American Heritage Dictionary
(1)
Century Dictionary
(3)
GNU Webster's 1913
(1)
WordNet
(1)
Elsewhere on the web
The utility said a 147-acre retention pond leaked water laced with calcium sulfate, a component of gypsum, which is released when coal burns.— Top Stories - Google News
It is often made from gypsum, a common mineral that can be mined or manufactured from the byproducts of coal-fired power plants.— Marketplace
That would be gypsum, the name given to the soft mineral - a combination of calcium sulfate and water - that has been excavated and mined in Kansas since the 1860s.— LJWorld.com stories: News
The gypsum, a material commonly used in wallboard, is stored dry in a nearby landfill.
Known as dihydrate in construction chemistry, gypsum is a water-containing ...— PhysOrg.com - latest science and technology news stories

American Heritage Dictionary (1)
Century Dictionary (1)
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