COLLECTIONS IN ECONOMIC GEOLOGY AND METALLUKGY. 35 



ORES. 

 True Ziervogel ores. 



(1) Basic sulphide ore, chalcopyrite showing some docom position, with a little 

 quartz. Contains 30 ounces of silver per ton and :<50 per cent, of copper. Gunnison, 

 County, Colorado. (55947.) 



(2) Basic oxidized ore, impure silicate of copper. Contains 50 ounces silver per ton 

 and ;}0 per cent, of copper. New Mexico. (55952.) 



(3) Siliceous ore, quartz stained by decomposition products and containing some 

 unaltered sulphides. Contains 50 ounces silver per ton and 6 per cent, of copper. 

 Montana. (55955.) 



Ziervogel ores containiny (/old. 



(1) Basic sulphide ore, tetrahedrite, chalcopyrite, galena, and quartz. Contains 

 2 ounces gold, 100 ounces silver per ton, and 10 per cent, of copper. Gunnison 

 County, Colorado. (55946.) 



(2) Basic sulphide ore, pyrite, chalcopyrite, with a little quartz. Contains 5 to 10 

 ounces gold, 20 ounces silver per ton and 5 per cent, of copper. ' Gilpin County, Colo- 

 rado. (55949.) 



(3) Siliceous ore, quartz containing tetrahedrite and stained by salts of copper. 

 Contains 1 ounce gold, 20 ounces silver per ton and 6 jier cent, of copper. Utah. 

 (55956.) 



Siliceous ores for mixture with first matte in the fusion for second matte. 



(1) Iron-stained quartz. Contains 50 to 100 ounces of silver per ton. Robert E. 

 Lee Mine, Leadville, Lake County, Colorado. (55944.) 



(2) Quartz, with a small amount of sulphides. Contains .50 to 100 ounces of silver 

 per ton. Clear Creek County, Colorado. (55950.) 



(3) Quartz, stained by decomposition products. Contains 50 to 100 ounces of silver 

 per ton. Gilpin County, Colorado. (55951.) 



Complex and refractory ore. 



(1) Basic sulphide ore, galena, blende, and pyrite. Contains 50 ounces of silver per 

 ton. Robinson Mine, Colorado. (55943.) 



liich sulphuretted gold ores for mixture with leached residue for fusion. 



(1) Siliceous ore, chert mixed with sulphides and tellurides; very complex ore. 

 Contains 5 to 10 ounces of gold, and 100 to 500 ounces of silver per ton. Bassick 

 Mine, Rosita, Custer County, Colorado. (55945.) 



(2) Siliceous ore, quartz with some sulphides. Contains 5 to 10 ounces of gold and 

 20 to 50 ounces of silver per ton. Boulder County, Colorado. (55948.) 



Basic ores, valuahlc on account of their fluxing properties. 



(1) Oxide of manganese and quartz, concentrates. Contain 50 to 100 ouncesof silver 

 per ton. Silver Cliflf Mine, Rosita, Custer County, Colorado. (55954.) 



(2) Sulphide ore, pyrite and chalcopyrite, concentrated from the gold ores of Gil- 

 pin County, Colorado. Contains 1 ounce of gold and 3 ounces of silver per ton. 

 (55953.) 



(3) Roasted sulphide ore, No. 55953, roasted in reverberatory furnace. (55958.) 



(4) Roasted ore, a mixture of Nos. 55943 and 55955. (55957.) 



FURXAOE SAMPLES. 

 First fusion. 



(1) Furnace chartje, mixture of the ores as prepared for the first smelting for matte. 

 . (55959. ) 



(2) First matte, produced by smelting the ore mixture, No. 55959. Contains 48 per 

 cent, of copper. (55963. ) 



