618 GEOLOGY AND MINING INDUSTRY OF LEADVILLE. 



Analysis I. — Adelaide ore. 



Oxide of lead 79.550 



Chloride of lead 0.990 



Peroxide of iron 0. 467 



Alumina 0. 444 



Protoxide of iron 0. 299 



Protoxide of manganese 0. 137 



Oxide of cobalt Trace 



Lime 0.303 



Magnesia 0. 068 



Gold Trace 



Silver 0.009 



Arsenic Trace 



Water 0.395 



Phosphoric acid 1.532 



Snlphuric acid Tiace 



Silica 0.651 



Carbonic acid 14.700 



Total 99.545 



(Hillebraud.) 

 Gold, ^ff of an ounce to the ton. 

 Silver, 2^ ounces to the ton. 



Discussion. — This analysis shows that the Adelaide ore is composed of: 



Carbonate of lead (PbO, CO;) 85.605 



Pyromorphito 3 (3PbO, PjOs) + Pb CU 9.748 



Carbonates, silicates, and oxides 4.647 



100. 000 

 All the coustitnents of these miuerals, which are widely distributed in Leadville, 

 will be traced later iu the analytical study of the smelting process. 



Analysis 11.— Little Chief ore. 



Oxide of lead 7.5.408 



Peroxide of iron 1 . 940 



Alumina 1. 415 



Oxide of cobalt Trace 



Protoxide of manganese 0.074 



Peroxide of manganese 1. 386 



Oxide of zinc 0.095 



Lime 0.335 



Magnesia 0. 056 



Silica 1.970 



Arsenic acid Trace 



Antimonic acid - 0. 121 



Water 1.140 



Carbonic acid 14.251 



Phosphoric acid Trace 



Sulphuric acid 0. 486 



Chlorine 0.288 



Silver 0.777 



Gold Trace 



Loss 0.258 



Total 100.000 



(Hillebraud.) 

 Silver, •iiiij 6V ounces to the ton. 



