Definition of kainite in US English:



  • A white mineral consisting of a double salt of hydrated magnesium sulfate and potassium chloride.

    • ‘An aqueous solution of kainite contains nothing except potash which, upon evaporation with platinum chloride, forms a compound which is insoluble in alcohol and the ammonium chloride wash ordinarily used in potash determinations.’
    • ‘This would have meant that the evaporation stopped at the kainite crystallization point.’


Mid 19th century: from German Kainit, from Greek kainos ‘new, recent’, because of the mineral's recent formation.