[ad. Germ. Abraum-salze salts to be removed.] Mixed salts found above the pure rock-salt at Stassfurt in Prussia, and also in the Isle of Wight, once thought useless, now used for producing chloride of potassium.
1753. Chambers, Cycl. Suppl., s.v. Abraum ... a species of clay, used in England … to give a red colour to new mahogany-wood.
1875. Ure, Dict. Arts, s.v. Abraum Salts … are employed on a very large scale for the production of chloride of potassium.
