double salt

American  

noun

Chemistry.

1. a salt that crystallizes as a single substance but ionizes as two distinct salts when dissolved, as carnallite, KMgCl 3 ⋅6H 2 O.

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double salt British  

noun

1. a solid solution of two simple salts formed by crystallizing a solution of the two salts Compare complex salt

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double salt Scientific  

1. A salt that crystallizes from an aqueous solution of a mixture of two different ions. The mineral dolomite (CaMg(CO ₃) ₂), for example, is a double salt that crystallizes from a solution containing both calcium and magnesium ions. Double salts exist only as solids.

2. Compare complex salt simple salt

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Etymology

Origin of double salt

First recorded in 1840–50

Example Sentences

It said that all 27 trunk routes in the south west of the country would receive double salt treatments at 13:00 and 01:00 throughout the week.

From BBC • Jan. 5, 2026

The difference between chrome alum and alum crystals is principally that chrome alum has twice the strength of alum crystals, being a double salt, instead of the commercial alum usually sold.

From Harper's Round Table, August 13, 1895 by Various

The salt of wisdom of the alchemists, a double salt composed of the chlorides of ammonium and mercury.

From Webster's Unabridged Dictionary by Webster, Noah

Small double salt and pepper earthen vessel, box-shaped, and decorated.

From Illustrated Catalogue of the Collections Obtained from the Pueblos of Zuñi, New Mexico, and Wolpi, Arizona, in 1881 Third Annual Report of the Bureau of Ethnology to the Secretary of the Smithsonian Institution, 1881-82, Government Printing Office, Washington, 1884, pages 511-594 by Stevenson, James

If the manganese is converted into the soluble double salt, prepared by adding an excess of potassium, and submitted to the electric current, the whole of the manganese will be deposited at the positive electrode.

From Scientific American Supplement, No. 299, September 24, 1881 by Various