Gypsum Rock
“From ancient seas to modern walls”
Gypsum rock is a soft sedimentary rock composed primarily of the mineral gypsum, which precipitates from evaporating seawater. It has been quarried for thousands of years and remains one of the most economically important sedimentary rocks — it's the raw material for plaster and drywall.
gypsum (calcium sulfate dihydrate, CaSO₄·2H₂O), anhydrite, clay, calcite
Paris Basin (France), White Sands (New Mexico, USA), Naica Mine (Mexico), Nova Scotia (Canada), Oman
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The Naica Mine in Mexico contains gypsum crystals up to 12 meters long and weighing 55 tons — the largest natural crystals ever found, grown over half a million years in a superheated cave.
Test Your Knowledge
What unusual property allows massive gypsum crystals like those in Mexico's Naica Mine to grow so large?
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