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sylvite

American  
[sil-vahyt] / ˈsɪl vaɪt /
Also sylvin,

noun

  1. a common mineral, potassium chloride, KCl, colorless to milky-white or red, occurring in crystals, usually cubes, and masses with cubic cleavage, bitter in taste: the most important source of potassium.


sylvite British  
/ ˈsɪlvaɪt, ˈsɪlviːn /

noun

  1. a soluble colourless, white, or coloured mineral consisting of potassium chloride in cubic crystalline form with sodium impurities: it occurs chiefly in sedimentary beds and is an important ore of potassium. Formula: KCl

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of sylvite

1965–70; < Latin ( sal digestīvus ) Sylvi ( ī ) digestive salt of Sylvius ( Sylvian fissure ) + -ite 1; replacing sylvine < French