Caesium Chloride: Pollucite Boiled in Hydrochloric Acid, Caesium Taken Out with Antimony Chloride (Fleischmann, US 2,808,313)

Pollucite, the caesium ore, is boiled for a day in concentrated hydrochloric acid. Antimony trichloride added to the clear liquor throws down caesium alone as a yellow-brown double salt; plain water splits that salt into caesium chloride, which dissolves, and white antimony oxychloride, which is kept for the next batch. Result: caesium chloride, boiled down and fused. The patent purifies further with perchloric acid; that step is left out here, so the salt still holds a little antimony and other metals. Source: H. J. Fleischmann (Michigan Chemical Co.), US 2,808,313 (1957), Example I. Not given for this shortened route: yield and purity. Boiling concentrated hydrochloric acid is a strong acid. Picture drawn by Youblob.