white alkali

noun
  1. Agriculture. a whitish layer of mineral salts, especially sodium sulfate, sodium chloride, and magnesium sulfate, often occurring on top of soils where rainfall is low.
  2. refined soda ash.
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British Dictionary definitions for white alkali

white alkali

noun
  1. refined sodium carbonate
  2. any of several mineral salts, esp sodium sulphate, sodium chloride, and magnesium sulphate, that often appear on the surface of soils as a whitish layer in dry conditions
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