Celestine or Celestite is a mineral consisting of strontium sulfate. Named from the Greek "cœlestis," for celestial, in allusion to the faint blue color of the original specimen.
Celestine occurs as crystals, and also in compact massive and fibrous forms. It is mostly found in sedimentary rocks, often associated with the minerals gypsum, anhydrite, and halite.
The mineral is found worldwide, usually in small quantities. Pale blue crystal specimens are found in Madagascar.
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