BAIN.] 



SECONDARY MINERALS, 39 



Pyrite. — The iron sulphide, probably in the main i^yrite, FeS., is 

 as usual widely disseminated. It is, however, distinctly subordinate 

 in quantity, and in this particular the district is in contrast with many 

 of the mining districts of the West. 



Chalco pyrite. — The copper-iron sulphide, CuFeSo (sulphur, 35 per 

 cent; copper, 34.5 per cent; iron, 30.5 per cent; specific gravity, 

 4.1 to 4.3), occurs in minute quantities, and small crystals may fre- 

 quently be observed by carefully examining the ores. It is not of any 

 economic importance here. 



Stihnite. — The antimony sulphide, Sb^S^ (sulphur, 28.6 per cent: 

 antimony, 71.4 per cent; specific gravity, 4.52 to 4.62), has been re- 

 ported by Mr. Bisland, of the Fairview mine, and Filers mentions its 

 presence and also that of a mineral taken to be jamesonite. He speaks 

 of these as being in such small quantity as to interpose no difficulties 

 in smelting and to be of no value. 



SECONDARY MINERALS. 



Cerussite. — The lead carbonate is reported to have been found in 

 small quantities in the early days of the mining industry. It has 

 long since disappeared and probably never was abundant. 



Smithsomte. — Zinc carbonate, ZnCOs (carbon dioxide, 35.2 per 

 cent; zinc oxide, 64.8 per cent: specific gravity, 4.30 to 4.45), occurs 

 frequently in connection with the alteration of the blende. It is 

 a rusty-looking material, not unlike some of the weathered chert in 

 appearance, but readily distinguished by its weight. The only body 

 of any size noted in the course of the survey was at the Empire mine, 

 and the quantity present here, while undetermined, was not impres- 

 sive. 



Limonite. — The hydrous oxide of iron occurs in the region in con- 

 siderable abundance, and formerly there were two furnaces- the 

 Martha and the Illinois — making iron from it. The ores are low 

 grade, as judged by present standards, and, as they bear no obvious 

 relationship to the minerals mider investigation, were not especially 

 studied. Small bodies of im])ure iron oxide or ocher are here, as 

 usual, widespread. 



Malachite. — The (^opper carbonate, 2CuC03,Cu(OII)o, occurs as 

 a greenish stain at a number of points, particularly at the so-called 

 " copper vein " near Elizabethtown. The quantities observed were 

 everj^where inconsiderable. 



Copper. — Small flakes of native copper may be occasionally ob- 

 served in the Kosiclare ores. They seem to be due to local reduction 

 of the minute quantities of chalcopyrite. 



