224 
ANALYSES OF ROCKS, U. S. GEOLOGICAL SURVEY. 
[NO. 228. 
F. Meta-andesite tuff. Described in 14th Ann., p. 441. Contains 
plagioclase, augite, epidote, chlorite, and secondary hornblende. P. 
R. C. 719. 
G. Uralite-diorite, 1 mile southeast of Forbestown. Ornose. De- 
scribed in 17th Ann. , Part I, p. 521. Contains plagioclase, hornblende, 
and magnetite. P. R. C. 751. 
H. Basalt, Oroville, Table Mountain. Gamptonose. Described in 
14th Ann., p. 441. Contains plagioclase, olivine, augite, and magnet- 
ite. P. R. C. 718. 
1. Altered peridotite, 5 miles northeast of Strawberry Valley. 
Largely serpentine, with olivine, hornblende, magnetite, and calcite 
or dolomite. P. R. C. 742. 
Si0 2 .. 
AlA- 
Fe 2 O a 
FeO. 
MgO . 
CaO.. 
Na,< ) . 
K,0_. 
H 2 above 100° 
Ti0 2 
P 2 5 
CrA 
MnO 
NiO 
SrO 
BaO 
Li 2 
C0 2 
CI 
F 
S0 3 ... 
FeS, 
54.66 
15.85 
1.82 
5.12 
5.64 
8.75 
3. 46 
.47 
.25 
2.48 
.67 
.15 
.18 
trace? 
trace 
.04 
none 
.39 
51.07 
14. 93 
6. 44 
5.98 
4.84 
7.89 
5. 04 
.16 
.24 
1.73 
1.65 
.19 
trace 
trace 
trace 
.09 
ii. 
50.66 
13. 97 
2.55 
10.20 
4.45 
8.08 
3.32 
1.95 
.27 
.43 
2.39 
1.01 
.29 
trace 
trace 
.22 
none 
.02 
100. 02 100. 38 
14.81 
«1. 88 
1.98 
4.52 
30.91 
6.58 
.15 
.15 
6.88 
.02 
.29 
.13 
.09 
none 
none 
1.79 
99. 81 100. 18 
"Includes possible Ti0 2 . 
