I N I) E X 
Page. 
Abbott, J., reference to - 99 
Abrams, Mount, fissures near, course of. 50 
Adams claim, description of 256 
Alabama mine, description of 194 
Alaska mine, description of 195 
Alaskaite, occurrence of.. 84 
Alexandra mine, description of 2:J1 
Alunite, analysis of, from National Belle 
mine .. . 235 
Amador mine, description of 194-195 
American Belle mine. See National Belle 
mine. 
Analyses, alunite 235 
andesitic breccia L25 
cosalite 220 
kaolinite 234 
kobellite....' 257 
monzonitic porphyry 1 27 
water 114 
zunyite 7 < l 
Andesitic breccia, analysis of --- 12(5 
mineral composition of 126 
Andesitic rock, minei-al composition of . . 120 
Animas Forks, decline of 21 
Animas River, rocks exposed on 35 
Antiperiodic mine, description of 172 
Anvil Mountain, country rook at 139 130 
Arrastra Gulch, fissures in, course of i N 19 
gold on, discovery of. ... 10 
note on name of 145 
rock from, character of 11") 
Area discussed, climate of 25-26 
geographic position of 11 
geology of .. 30-39 
historical sketch of 19-25 
location of, map showing II 
maps of 26,32,34 
production of 25 
topography of 26 29 
vegetation in 2G 
Argall, P., cited _. 53 
Argentina mine, description of 213 
Argentite, occurrence and character of.. 83 
Aspen mine, description of 161 -It'.:! 
lode ores of __ 94 
ore in, depth of 98 
workings of, section of 162 
Baltic group of mines, description of . . 244-245 
Baker, J . , exploration by 19 
Bakers Park, view of 13 
Bancroft, H. H., cited 20 
Banded structure of ode ores, examples 
of 88-91 
Page. 
Barite, occurrence and character of 71-72 
Barstow mine, description of 246 
Bassick mine, ore body in, origin of 137 
Becker, G. F. , cited 42, 65, 66, 134 
Belcher mine, description of 252 
ore in, depth of.. 93 
Ben Butler mine, description of.. H6 
Ben Franklin mine, description of 178-179 
Benson, J. W., reference to. 202 
Bibliography 15-18 
Big Giant lode, description of 1 J6 
Bill Young mine, description of 137 
Bimetallist mine, description of 205 
Bismuthinite. occurrence and character 
of 82 
Black Diamond mine, description of 134 
Black Silver mine, description of 139 
Blair Gulch, fissures in, course of 48-49 
Bobtail mine See Barstow mine. 
Bonanza mine, description of. 196 
Bonanza tunnel, work on 21 
Bonita mine. See Red and Bonita mine. 
Bornite, occurrence and character of 80 
Bournonite, occurrence and character of. 8L 
Breccia, andesitic, analysis of 126 
mineral composition of . 126 
Brecciated structure of lode ores 91 
British Queen claim, description of 137 
Brobdignag claim, description of . 219 
Brooklyn tunnel, description of 245 
Brunot treaty, provisions of 20 
Buckeye lode, effect of depth on 93 
Buckeye mine, description of 160-181 
Bull Domingo mine, ore body in, origin 
of.. 107 
Burns Gulch, lodes of 174-176 
Calcite, occurrence and character of 72 
California Gulch, mining in ... ... 21 
Camp Bird lode, section through rich ore 
hand in . 90 
Camp Bird mine, banded ore at _. 89-90 
description of 200-204 
ore from, plates showing 72, 88 
ore in , occurrence of 97 
surface workings of, view of 20U 
Canyon Creek, fissures in, course of 50 
lodesof 200-205 
Carbonate King mine, description of 239 
Cataract Gulch, fault fissure in 57 
Cellular structure in lode ores 91 
Cement Creek, fissures near 50 
mines of 254-258 
springs, ferruginous, near 1 13 
259 
