INDEX 
511 
Page. 
Petrology of district. 101-113 
Petrology of metamorphic and igneous rocks.3,41-113 
Petzite, description of. 116 
occurrence of. 114 
Pharmacist Consolidated Mining Company, mine of... 399 
Pharmacist mine, description of. 399-401 
dipin. 156 
location of. 5,399 
minerals in. 123 
ore of. 400-401 
production of. 399 
rocks in. 34,400 
veins of. 149,393-395,400 
workings of. 399-400 
Pharmacist vein, character of. 159 
166,391,393,395,397,400,401 
ore shoots on. 212 
stereogram showing. 211 
Phonolite, abundancy of. Ill 
alteration of.... 184,188 
analyses of. 66,104 
area covered by. 110 
composition of. 66-67 
definition of. 57 
description of. 1,57-58 
dike of, intersection of sheeted zone and, ore at, 
figure showing. 212 
dikes of. See Dikes, phonolite. 
fissures in.,. 164 
intrusions of. 24,38,58 
minerals in. 67 
occurrence of. 1-3,19,20,34-37, ^7-58,98-99, passim 271-496 
origin of. 56 
petrology of. 59-67 
photomicrographs of. 60 
texture of. 58,65-66 
transition of, to latite-phonolite. 83-84 
Phonolitic breccia, occurrence of.20 
Photomicrographs of rocks. 60,82,94 
Pikes Peak, rush to. 130 
views of. 18,34,280,362 
Pikes Peak granite, analyses of. 45 
description of. 3,43,45-46,47,193 
fissures in. 159 
occurrence of. 20,23,29,34, 
279,281,314,334,337,349-352,356-358,430,467,495 
petrology of. 43-45 
Pikes Peak mine, production of. 380 
workings of. 382 
Pikes Peak vein, location of. 149,411 
Pilgrim tunnel, rocks in. 88 
Pinnacle mine, description of. 383-384 
location of. 149,383 
veins ir^, character of. 206,383-384 
workings of. 383 
Pinto dike, location and description of. 93, 
166,212,393,394,396-397,399 
ore shoots on. 36 
stereogram of. 211 
Pinto mine, description of. 396 398 
dikes in. 36,97,396 
geology of. 396-397 
location of. 396 
ore of...-. 212 
veins of. 397-398,411 
stereogram showing. 211 
workings of.-. 396 
Pinus, occurrence of. 31 
Page. 
Pisgah, Mount, rocks of. 34,97 
view of. 18 
See alio Mount Pisgah mining district. 
Placers, occurrence of. 5,152 
Plagioclase, occurrence of. 43-44,46,47,49,72,73,86,93 
Plymouth Rock mine, description of. 285 
location of. 148,285 
minerals in. 174 
oxidation in. 197 
workings of. 285 
Pointer mine, description of._. 306-308 
dike in. 95 
gas in. 262 
minerals in. 121,122,124 
ore of. 171,174,307-308 
rocks in.1. 32,306-307 
veins in, character of. 162,179,307-308 
workings of. 306 
Pointer vein, location and description of. 307 
Porcupine shaft, location of. 382 
Porphyries, character of. 2 
occurrence of. 2,20 
Porter Gold King mine. See E. Porter Gold King 
mine. 
Portland mine, description of. 430-449 
dikes in. 438-439 
structure of, plate showing. .<. 166 
chlorination mill at, process in. 142 
development of. 133 
dikes in. 91,93,95,381 
drainage of. 242,449 
geology of. 433-439,457 
map showing. 434 
history of. 131,144-145,430-431 
locating of. 4,430 
location of. 5,150,430 
minerals in. 116,118,120,121,122,126,128,129 
mining in. 135-136 
ore of. 171,172,174,208,212,214,442-448 
value of. 448 
plan of. 432 
production of. 135,150,431 
rocks in. 27-29,32,33,85,98,209 
analyses of. 79,87 
sections of, figures showing. 140,433 
sorting at. 137 
valuation of. 144 
veins in, character of. 154,157,159,160,162, 
163,164,173,174,177,179,205,439-442,443-448,452 
figure showing. 162,164,166 
view of. 430 
water level in. 197,234,240,449 
change in. 242 
figure showing. 242 
workings of. 431-433 
maps showing. 432,434 
Portland vein, location and description of. 435, 
438,439,440,446 
Potassium, presence of, in vein-forming water. 222-223 
Potter vein, character of. 292,294 
Poverty Gulch, dikes in. 32,271-272 
drainage of. 244 
exploration in. 130,131 
gold in. 4 
mines in. 5,147,271-279 
oxidation in.*. 198 
rocks in. 25,32,70,271 
Precipitation, amount of. 233 
