VIII.—On the Preparation of a Cheap Heavy Liquid, for the Separation of Minerals

Extract

The high price of all heavy liquids, and the consequent care that has to be taken in using them, the latter of course entailing great expenditure of time, were the reasons which caused me to make experiments, with regard to the manufacture of Klein's solution (borotungstate of cadmium) on a small scale. The price quoted in a well-known chemical manufacturer's price-list is 3s. 6d. per oz. My experiments have shown me that it can be made for about 7d. per oz., plus the value of the time of the maker. The process is very simple, and not much time is necessary in making it. A rough outline of the method of preparation is given by Dr. Klein in the Comptes Rendus, vol. xciii. August, 1881.