Bittern (salt)

Bittern (pl. bitterns) is a bitter-tasting solution that remains after evaporation of halite (common salt) from brines and/or seawater. It is rich in magnesium chlorides, sulfates, bromides, iodides, and other chemicals present in the original waters.

Bittern has been extracted for a long time, at least several centuries. The Dutch chemist Petrus Jacobus Kipp experimented with saturated solutions of bittern. The term for the solution is a modification of "bitter".

Bittern is used to culture Haloquadratum bacteria. It is also used for extraction of epsom salts and other mineral salts.

The solution can furthermore be used in the production of potash and potassium salts.

Bittern, when the product of salt production, appears to have no adverse effects on the environment. It comes from seawater and can safely be returned to the sea, although bitterns are sometimes used instead to produce fertilizer.

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