CLARKE.] 
IGNEOUS AND CRYSTALLINE ROCKS. 
125 
B. Granite-porphyry, Wolf Butte. Phenocrysts of quartz, ortho- 
clase, plagioclase, and biotite in a groundmass of quartz and alkali 
feldspar. A little apatite and iron ore, with secondary calcite, limon- 
ite, chlorite, and white mica. Analysis by Stokes. 
C. Granite-porphyry, top of Barker Mountain. Phenocrysts of 
orthoclase, oligoclase, biotite, green hornblende, sphene, and iron ore 1 , 
in a groundmass of quartz and alkali feldspar. Also a little apatite 
and some secondary chlorite and limonite. Analysis by Stokes. 
D. Syenite, Wright and Edwards mine, Hughesville, near Barker. 
Very fresh rock. Contains magnetite, ilmenite, hornblende, anortho- 
clase, albite, subordinate quartz, a little chlorite, calcite, and limonite, 
and white mica in traces. Analysis by Stokes. 
E. Syenite, Yogo Peak. Described in Amer. Journ. Sci. , 3d series, 
vol. 50, p. 471. Contains apatite, sphene, iron ore, pyroxene, horn- 
blende, biotite, orthoclase, oligoclase, and quartz, with traces of chlo- 
rite and limonite and a little kaolin. Analysis by Hillebrand. 
F. Syenite-porphyry, dike at head of Sheep Creek. Phenocrysts of 
orthoclase, some plagioclase, and green hornblende, in a groundmass 
of alkali feldspar, with some quartz. Also contains a little apatite 
and iron ore, with some secondary calcite and kaolin. Analysis by 
Hillebrand. 
A. 
B. 
c. 
D. 
E. 
F. 
Si0 2 
73.12 
14.27 
.51 
.26 
.24 
1.10 
3.43 
4.90 
.68 
.73 
.08 
.03 
none 
.06 
trace 
trace 
trace 
.77 
69.68 
14.97 
.79 
.34 
.66 
2.10 
3.38 
4.40 
1.09 
.92 
.28 
.17 
68.60 
16.13 
2.22 
.44 
.72 
1.36 
4.37 
4.89 
.20 
.58 
.32 
.18 
64. 64 
16.27 
2.42 
1.58 
1.27 
' 2.65 
4.39 
4.98 
.09 
.27 
.51 
.37 
61.65 
15.07 
2.03 
2.25 
3.67 
4.61 
4.35 
4.50 
.26 
.41 
.56 
.33 
trace 
.09 
.10 
.27 
trace 
66.29 
15. 09 
1.37 
1.17 
2.39 
2.38 
3. 96 
4.91 
.39 
.60 
.27 
.15 
none 
.06 
.07 
.30 
trace 
.45 
A1 2 3 ----*--- 
Fe 2 3 
FeO 
MgO 
CaO 
Na 2 
K 2 
H 2 Oatll0 o ... 
H 2 above 110° 
Ti0 2 
P 2 0, '.... 
Cr 2 3 ... 
MnO 
trace 
.06 
.14 
trace 
.88 
trace 
trace 
trace 
.09 
.27 
trace 
trace 
.08 
.18 
SrO 
BaO 
Li 2 .. 
C0 2 
SO, .. 
.37 
trace 
.05 
trace 
trace 
CI... 
100. 18 
99.86 
100. 37 
100. 12 
100. 15 
99.85 
