Astringent Crystalline Substance Crossword

Astringent crystalline substance crossword clue. A two speed crossword question in Herald Sun on Monday, 26 June 2017. 5 letters. Also appear on Daily Telegraph/Courier-Mail.

Answer: ALUMS

Alums are useful for a range of industrial processes. They are soluble in water, have a sweetish taste, react acid to litmus, and crystallize in regular octahedra. In alums each metal ion is surrounded by six water molecules. When heated, they liquefy, and if the heating is continued, the water of crystallization is driven off, the salt froths and swells, and at last an amorphous powder remains. They are astringent and acidic.