Proceedings of the Royal S(jclety of Victoria. 



r.. ... Metallic minerals in order of 



D'st"ct. relative abundance. 



Mallacoota ... Liiiionite, pyrite, bismixtite 



Beiiiui River . . . Arseuopyrite, pyrite, galena, blende . . . 



Mount Tara . . . Pyrite, limonite, barytes 



Moimt Wills .. Pyrite, stibnite, arsenopyrite, argen- 



tite, cerargyrite 



Cassilis Arsenojjyrite, blende, pyrite, galena . . . 



Haunted Stream Arsenopyrite, pyrite, galena, blende . . . 

 Deptford ... Do. do. do. 



Bullumwaal ... Arsenopyrite, pyrite, galena, blende, 



and wad 

 Grant ... . Arsenopyrite, pyrite, galena, blende, 



and wad 

 Dargo ... .. Arsenopyrite, i^yrite, galena, blende, 



wad, and erythrite ... 

 Budgee ... Arsenojiyrite, pyrite, galena, blende, 



chalcoi^yrite ... 

 Walhalla ... Arsenopyrite (needle pyrites), pyrite, 



bournonite, galena, blende 

 Wood's Point . . . Pyrite, arsenopyrite, stebnite, siderite 



Standard 



of ffold 

 per 100. 



96 



85 

 80 



GG to 76 



m to 80 



90 to 9G 



96 



70 to 95 



82 

 82 to 97 



As a general rule, from 1 to 5 per cent, of concentrates is 

 obtained from raw ore, yet in the case of the Cassilis lodes the 

 percentage of metallic mineral contents may rise to 50 per cent. 

 Parcels of concentrates from Glen Wills have contained 25 ozs. 

 gold and 90 ozs. silver per ton, yet the usual returns, when 

 crushing from ounce stone, will be from 2 to 5 ozs. per ton of 

 concentrates. 



The gold in the ore is an alloy of gold and silver, containing 

 from 66 per cent, of gold to 97 per cent, in the highest gi'ades ; 

 only very minute quantities of copper, iron, lead and bismutii 

 are to be detected. Copper is certainly a natural alloying 

 element, but iron and lead are probably oxides or sulphides 

 mechanically mixed only. 



As Mr. Howitt pointed out, the gold ratio is invariably higher 

 when occurring in sedimentary formations than when associated 

 with granites or diorites. 



The separate parcels of ore are weighed and samples are 

 taken and dried at 110° C, and carefully assayed. The total 

 weight and value of each lot is thus determined. The ores are 

 then blended according to their composition, care being taken to 



