98 
ANALYSES OF ROCKS, U. S. GEOLOGICAL SURVEY. [bull. 16; 
E. Augite-andesite, Dike Mountain. Contains augite, plagioclase 
serpentinized olivine, magnetite, and apatite. 
F. Trachyte-andesite, Dike Mountain. Contains plagioclase, ortho 
clase, chlorite, apatite, and magnetite. Very little augite. 
G. Biotite-trachytc, Dike Mountain, 
clase, biotite, magnetite, and chlorite. 
H. Biotite-trachyte, Dike Mountain, 
clase, biotite, and magnetite. 
Contains plagioclase, orthc 
Contains orthoclase, plagio 
Si0 2 
A1 2 3 
Fe 2 3 
FeO 
MgO 
CaO 
Na 2 
K 2 
H 2 OatllO°... 
H 2 above 110° 
Ti0 2 
PA 
Zr0 2 
Cr 2 3 
v 2 o 3 
NiO 
MnO 
SrO 
BaO 
Li 2 
C0 2 
FeS 2 
51.17 
16.14 
4.11 
4.48 
4.82 
7.72 
2.99 
3. 54 
.63 
2.24 
1.01 
.48 
none 
trace 
.04 
.01 
.21 
.10 
.20 
trace 
none 
.05 
99.94 
52.47 
18.23 
3.31 
3.85 
2.85 
4.56 
4.83 
3.81 
.68 
2.03 
.97 
.64 
.02 
trace 
.03 
trace 
.15 
.11 
.23 
trace 
1.01 
.04 
99.82 
63.24 
17.98 
2.67 
.85 
.63 
.93 
6.27 
5.47 
.37 
.80 
.38 
.22 
trace 
none 
.01 
none 
.04 
.03 
.25 
trace 
none 
trace 
100. 14 
H. 
57.73 
18.93 
1.97 
1.92 
.91 
2.78 
5.52 
6.11 
.22 
2.93 
.33 
.25 
trace 
trace 
.01 
trace ? 
.06 
.09 
.16 
trace 
.26 
.02 
100. 20 
