IGNEOUS AND CRYSTALLINE ROCKS. 95 
14. PHILIPSBURG QUADRANGLE. 
Rocks collected by F. C. Calkins, who supplies the petrographic data. 
A. Quartz monzonite, Royal mine. Contains quartz, plagioclase, orthoclase, and 
biotite, with accessory muscovite, magnetite, apatite, zircon, and tourmaline. 
B. Quartz monzonite, from head of east fork of Rock Creek. Contains quartz, plagio- 
clase, orthoclase, biotite, and a little hornblende, with accessory apatite, zircon, 
titanite, and magnetite. 
C. Quartz monzonite, from a quarry one-half mile southwest of Cable mine. Con- 
tains plagioclase, alkali feldspar, quartz, biotite, hornblende, and pyroxene, with 
accessory magnetite, apatite, and zircon, and secondary chlorite, epidote, calcite, 
kaolin, muscovite, and titanite. Analyses A, B, C, by G. Steiger, record No. 2367. 
D. Pyroxene aplite, about 1 mile northeast of Rumsey Mountain. Contains plagio- 
clase, quartz, orthoclase, pyroxene, titanite, scapolite, apatite, and zircon. 
E. Scapolite-pyroxene aplite, from cliff east of Foster Creek, about one-half mile 
north of the county boundary. Contains scapolite, plagioclase, quartz, alkali feldspar, 
pyroxene, hornblende, titanite, apatite, and zircon, with secondary calcite, epidote, 
and sericite. Analyses D, E, by W. F. Hillebrand, record No. 2365. 
IDAHO. 
Rocks A to K, inclusive, are described by Waldemar Lindgren in 20th Ann., pt. 3, 
. 75. 
: A. Quartz monzonite, Idaho-Democrat mine, Hailey. Toscanose. Contains quartz, 
orthoclase, microcline, oligoclase, biotite, apatite, titanite, and magnetite. Sp. gr., 
2.672, 27.5°. 
B. Same rock and locality as A, but in altered condition. Contains quartz, sericite, 
chlorite, calcite, pyrite, rutile, etc. Sp. gr., 2.472, 29°. 
C. Diorite, Creesus mine, Hailey. Andose. Contains labradorite, biotite, diallage, 
hypersthene, hornblende, quartz, titanite, magnetite, orthoclase, and chlorite. Sp. 
gr., 2,826, 28°. 
D. Same rock and locality as C, but in altered condition. Contains quartz, sericite, 
chlorite, calcite, pyrite, arsenopyrite, rutile, etc. Sp. gr., 2.898, 28°. 
Analyses A to D by W. F. Hillebrand, record No. 1826. The metals which are 
bracketed with sulphur represent sulphides. Traces of lithia are present in all four. 
