PRESIDENT S ADDRESS — SECTION B. 123 



localities were fitted for hopeful experimenting. In fact, so great were 

 the obstacles from one source or another that the whole scheme fell 

 into serious disrepute. 



Pyrite Smelting. — The revival, however, came in due time, brought 

 about by economic conditions, in the smaller mining districts of the 

 United States. Here the special circumstances of ore supply, and 

 particularly the great lack of lead, were locally causing a reintroduction 

 of " pyritic smelting " (or Eoharbeit), in the older sense of raw smelting, 

 for the concentration of the precious metals in a matte, with this 

 significant difierence, however, that the presence of copper was now 

 encouraged, because its value as a collecting medium had meanwhile 

 become fully appreciated. In view of the great cost of coke. &c., the 

 interest in the rapid oxidation of sulphide ores as spontaneous fuels, 

 was revived by W. L. Austin. He and others took up the raw-smelting 

 innovation, and perfected it in the new light ; for the temptation to 

 force the pyrites to act in a threefold capacity of fuel, flux, and collect- 

 ing vehicle was too near-lying. Following in the footsteps of Mr. 

 Hoi) way, and modernising his operative scheme, the true pneumatic 

 pyritic principle, but supported by the use of a hot blast, was at last 

 brought to some degree of practical perfection, with as much success 

 as a renewed multitude of untoward obstacles of every possible nature 

 permitted. This was effected in Montana, from 1887 to 1891, and 

 subsequently further pursued in Colorado. The chief drawback con- 

 tinued to be a dearth of pyrites. The method also again met with the 

 usual reluctant attitude on the part of the established copper smelters, 

 who feared heavy copper losses by scorification, although the daily 

 evidence of their copper converters, properly transferred to the new 

 blast-furnace scheme, ought to have convinced them of the contrary. 



It was, however, reserved for Australia to demonstrate, finally and 

 conclusively, that " pyritic smelting " in the newer sense, or, more 

 properly, " pyrite smelting," is wholly suitable for copper ores of any 

 grade, and is not afflicted with a greater wastefulness through scorifica- 

 tion, or any other source, than current older methods, either the Welsh 

 process or the roast-reduction process — on the contrary. The special 

 opportunity came at Mount Lyell, Tasmania, in 1896, where the pneu- 

 matic blast-furnace treatment of a heavy pyrite, with 4|- per cent, of 

 copper, it may be said, settled the scorification bogy in a couple of 

 hours after the first furnace was started, i.e., through the freedom 

 from copper of the first slag that ran out. Since that time the process 

 has been permanently taken up by the companies beneficiating the 

 larger pyritic ore bodies of the world (Rio Tinto, Ducktown, Keswick, 

 Kosaka, Sulitjelma, Cobar, Clifton, and others, in some cases with 

 local modifications of apparatus and procediu"e), though it may be 

 claimed that, so far, the honor of greatest fidelity to the ideal features 

 of the method is unreservedly Australia's. 



The process, as at present carried out, is, however, not as perfect 

 as it might be, chiefly because the full energy of reaction which pyrites 

 and sihca in proper proportions are capable of is not yet excited by the 

 methods and appliances employed. The main defect is the necessity 

 of still using at least a modicum of carbon. Complete emancipation 



