INDEX. 
515 
Page. 
Trotter claim, location of. 415 
Troutman, Fred, development by. 131 
Tuff, occurrence of. 98 
Tunnels, drainage, construction of. 235,246-247,250-251 
discharge by. 235-238,239-251 
figures showing. 236,242 
effect of. 9-10,239-246 
figures showing. 236,242,250 
location of. 235 
possible locations for. 246-247,249-251 
U. 
Union Gold Mining Company, mines of. 380 
United States Reduction end Refining Company, 
plant of, process in.,. 140-142 
V. 
Valencianite, occurrence of. 443,464 
Van Hise, C., on deposition. 231 
on gneiss. 48 
on tellurides. 223-224 
Vaughn shaft. See Glorietta shaft. 
Vein formation, alteration due to. 184 
Veins, composition of. 229 
formation of. 216 
intersections of, ore deposits at. 209-213 
metasomatism and, relations of.7,184-185 
minerals in. 114-129,173-176 
oxidation of. 198-199 
pitch of. 206 
structure of. 160-165,176-182 
plates showing. 160,162,164,166 
See also particular mines: Lode fissures. 
Ventilation, provision for. 253 
provision for, sections showing. 263 
Venture Corporation, mine of. 450 
Victor, fissures near. 154 
mines in and near. 5,476,477,487 
rocks near. 24 
view of. 34 
Victor Consolidated claims, location of. 478 
Victor Gold Mining Company, mines of. 387 
Victor mine, description of. 387-388 
geology of... 387 
location of. 5 
map showing. 388 
minerals in. 123 
ore in. 213,388 
production of. 149,387 
veins of. 156,387-388 
water level in. 234,244,245 
workings of. 387 
Vindicator Consolidated Gold Mining Company, mine 
of. 415 
Vindicator mine, description of. 415-422 
dike in. 95 
geology of. 416-417 
location of. 5,149,408,415 
metasomatism in. 190-191 
minerals in. 120,121,122.126,129 
ore of. 208,212,213,418 
oxidation in. 198,416 
production of. 149,415 
rocks in. 32-33,34,85 
analysis of. 189 
section of, figure showing. 420 
temperatures in.. 270 
Page. 
Vindicator mine, veins in, character of.156, 
157,158,173,206,417-422 
view of. 362 
water level in. 198,240,245,246,416 
change in, figure showing. 242 
workings of. 408,415 
figure showing. 419 
Vindicator vein, location and description of. 159,266 
production of. 159 
Virginia M. vein, location and description of. 309,310-311,312 
Vogesite, abundancy of. Ill 
analyses of.95,104 
area covered by. 110 
composition of. 93,95 
description of. 93 
occurrence of... 3,93,393 
origin of. 56 
photomicrograph of. 94 
petrology of. 93 
Volcanic cone, erosion of. 39-40 
formation of. 25,38 
• outline of. 25,38,40 
sections showing. 39 
Volcanic eruptions, date of. 1,2,23 
effects of. 2,21,24-25,36,38 
location of. 1,20,24 
products cf. 1,3,21 
Volcanic neck, carbonized wood in. 32 
fissures in. 154 
form of. 21,24-30 
intrusions in. 32 
Volcanic rocks, alkali-alumina and soda ratios of. 106 
alteration of. 184-185 
alumina-silica ratios of. 107 
analyses of. 66,79,87,90,93,95,96,104, 111 
discussion of. 20 
areas covered by. lio 
average rock of, composition of. 109-112,113 
composition of.. 66-67,79-83,87-88,90,92-93,95,96,104-112 
diagrams showing. 112 
explanation of. 107-109 
description of. 56-58,67,68-71,84-85,88-89,90-91,97-98 
divisions of. 56-57 
minerals in. 103 
occurrence of. 57-58,70,100 
origin of. 1,3,21,35-36,38,43 
oxides in. 105 
petrology of. 59-65,67-68, 
71-78,83-84,85-87,89-90,91-96,98-101,102-113 
potash-soda ratio of. 105 
succession of, order of. 113 
texture of.65, 78 
See also Igneous rocks. 
Volcano, exhalations from. 10,257-258 
Vulcan claim, location of. 349 
W. 
Wacu Weta mine, description of. 404 
Wad, description of. 123 
origin of. 201 
Wages, status of. 5 
Walden, Charles, data from. 375 
Wallace claim, location of. 415 
Wallace vein, location and.description of_ 417, 418, 421-422 
Walter claim, location of. 331 
Walter vein, location and description of. 164 
166,175,317-318,321,332-333,336-338 
Wardell vein, character of. 294-295,297 
