Rock Salt (Halite)
“The edible rock”
Sedimentary
Rock salt, or halite, is an evaporite sedimentary rock formed when bodies of saltwater evaporate, leaving behind thick deposits of sodium chloride crystals. These deposits can be hundreds of meters thick and millions of years old.
Composition
halite (NaCl), traces of gypsum, anhydrite, clay
Where Found
Wieliczka (Poland), Khewra (Pakistan), Salzburg (Austria), Louisiana (USA)
Mohs Hardness
2-2.5
Fun Fact
The Wieliczka Salt Mine in Poland contains an entire underground cathedral — altars, chandeliers, and sculptures — all carved from rock salt.
Test Your Knowledge
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