syl·vite 
(sĭlvīt′) also syl·vine (-vēn′) or syl·vin·ite (-vĭ-nīt′)
(sĭlvīt′) also syl·vine (-vēn′) or syl·vin·ite (-vĭ-nīt′)n.
A colorless vitreous potassium chloride mineral, the major ore of potassium.
[Alteration of sylvine, from French, from New Latin (sāl dīgestīvus) Sylviī, (digestive salt) of Sylvius, probably after Franz de la Boë, or Franciscus Sylvius (1614-1672), German-born Dutch physician.]