CLARKE.] 
IGNEOUS AND CRYSTALLINE ROCKS. 
229 
L. Bleached country rock, next to vein, Osborne Hill mine. Derived 
from sandstone. Analysis by George Steiger, record No. 1541. 
M. Altered wall rock, Empire mine. Derived from granodiorite. 
Analysis by Steiger, No. 1541. Sp. gr., 2.782, 20°. 
N. Altered wall rock, Ebaugh tunnel. Derived from granodiorite. 
Mainly quartz and sericite, with pyrite, apatite, sphene, and carbonates. 
Analysis by Steiger, No. 1541. Sp. gr., 2. 747, 20°. 
O. Altered wall rock, Federal Loan mine. Derived from siliceous 
argillite. Analysis by Steiger, No. 1541. 
Si0 2 
ALA -- 
Fe 2 3 
FeO 
MgO 
CaO 
Na 2 
K 2 
H 2 Oat 100°.... 
H 2 above 100° 
Ti0 2 
PA 
MnO 
BaO 
SO-3 
co 2 
FeS, 
L. 
M. 
N. 
71.97 
58. 43 
56. 25 
15. 75 
17. 40 
17. 65 
. 77 
.77 
.76 
.45 
2.19 
2.64 
.80 
1.50 
1.69 
.80 
5.25 
4.46 
. 33 
1.76 
.30 
4.88 
4. 03 
6.01 
.30 
.30 
.30 
2.16 
2.61 
2.36 
.88 
none 
.25 
.15 
.13 
.21 
none 
none 
none 
trace 
none 
.03 
trace 
none 
none 
.38 
4.04 
4.82 
.56 
1.59 
2.87 
100. 18 
100. 00 
100. 60 
34.91 
15.55 
.17 
4.96 
4.58 
11.10 
.19 
4.28 
. 30 
1.86 
1.65 
.82 
none 
none 
none 
15.57 
4.20 
100. 14 
