CHEMISTEY OF THE WASHOE PEOCESS. 293 



The following is the result of an analysis of some artificial crystals of 

 Washoe amalgam : 



Mercury 75.04 



Silver 24.18 



Gold 77 



They have the composition very closely of three atoms of mercury to 

 one of silver. 



From the foregoing considerations of the principal features of the Washoe 

 process it appears — 



That the ore consists chiefly of native gold, native silver, and argen- 

 tiferous sulphiirets, associated with varying proportions of blende and galena. 



That the action of chloride of sodium and sulphate of copper in the pan 

 produces chloride of copper. 



That the presence of metallic iron necessarily causes the formation of the 

 sub-chloride of copper. 



That both the chlorides of copper assist in the reduction of the ore by 

 chloridizing the sulphurets of silver, and in decomposing the sulphurets of 

 lead and zinc. 



That sulphate of copper enhances the amalgamating energy of mercury, 

 by causing the formation of a small quantity of copper-amalgam. It also tends 

 to expel the lead. 



That notwithstanding the importance of chemical agents, as above indi- 

 cated, the quantities added to the pulp in the ordinary practice of Washoe 

 mills are too small to efiect any very beneficial results. 



That mercury and iron, aided by heat and friction, are the principal 

 agents in the extraction of the precious metals by the Washoe process. 



That the essential conditions in the amalgamation of the gold and silver 

 are that the mercury be kept perfectly bright and pure, in order to produce a 

 direct contact of that metal with the iron and sulphide of silver. 



That the consumption of mercury in the Washoe process may be con- 

 sidered chiefly a mechanical, and, only to a limited extent, a chemical, loss. 



