50 Chlorine as a Solvent of Gold. 



The chlorine process, upon the success of which my late 

 friend built all his hopes, is, so far as I can remember it, and 

 so far as I have carried it out privately with him, and since 

 his lamented death, the following : 



Large wooden, or what is better, brick funnels, are filled, 

 each with any quantity, say from ten tons to fifty tons of 

 finely pulverized quartz, previously roasted and deprived of 

 its coarsest gold, by sieving or sluicing. The chlorine gas, 

 generated in a small cast-iron retort, of the capacity of two 

 or three cubic feet (greater if it be found more advan- 

 tageous), is forced into the funnels, and ascends through the 

 quartz from the bottom upwards. 



The action of the gas on the gold is very powerful. The 

 energy of the reaction is in a degree not unlike combustion. 



The gold is transformed into the per-chloride, which is very 

 soluble in water. 



This per-chloride of gold is washed out by water, fil tering 

 slowly through the quartz from the top of the funnel, and 

 falling into a receiver. From this solution all the gold is 

 precipitated by means of a small quantity of sulphate of the 

 protoxide of iron, the common green vitriol of the shops. 

 The gold falls in the form of a brown powder, which on 

 being fused in a crucible yields pure gold, twenty-four 

 carats fine. Such is the process. 



It may be in the recollection of some who are now pre- 

 sent, I feel sure it is not forgotten by our respected secretary, 

 who on one occasion assisted in this room to explain to a 

 meeting, Count Dembinski's process, that he proposed to 

 generate chlorine in the following manner : Finely pul- 

 verized quartz tailings are mixed with a common 

 salt, and heated in a closed vessel to fusion, in the 

 presence of super-heated steam. The reactions which take 

 place yield silicate of soda and muriatic acid, which is col- 

 lected in the usual manner. This is then worked up with 

 per-oxide of manganese, and the chlorine set free. 



During the latter weeks of his life, I suggested to him a 

 simpler and cheaper process, one which would dispense with 

 the use of any acid, save that of silicic, the quartz, and 

 this was at once adopted. 



This suggestion was to form a mixture of crude common 

 salt (chloride of sodium), per-oxide of manganese, and silica, 

 in proportion such as to form a double silicate, viz., a silicate 

 of soda, and a silicate of the protoxide of manganese. 



A mixture of one hundred parts of common salt, seventy- 



