Calcium morphenate is a calcium salt of morphine which is produced by using calcium bases to raise the pH of an aqueous solution of opium alkaloids to around 9.0.[1] This was a method used in pharmaceutical manufacturing to separate morphine from other alkaloids and inert materials from the opium solution. Variations on this route are still used in Afghanistan.[2] When poppy straw concentrate or opium latex is dissolved in hot water and the calcium base is added, calcium morphenate is formed. Treatment with a weak acid such as ammonium chloride then causes morphine freebase to precipitate, leaving codeine and other alkaloids of the plant in solution.