250 
ANALYSES OF ROCKS, IT. S. GEOLOGICAL SURVEY. 
[no. 228. 
L. Serpentine. 
M. Tale-like, yellowish-green serpentine. 
N. Weathered serpentine. 
O. Olive colored, probabty serpentine. 
Samples H, I, and J are from near Bag-ley Creek; K, L, M, and N 
from near Arroyo del Cerro; O from Ferguson ravine. M and O 
cany considerable chromite. 
L. 
M. 
N. 
0. 
Si( )., - 
34.84 
.42 
6.08 
1.85 
30.74 
7.02 
.42 
.07 
1.67 
15. 72 
.04 
.68 
trace 
.01 
32.27 
11.45 
trace 
5.05 
33.30 
.41 
trace 
trace 
.44 
12.40 
trace 
5.19 
.19 
trace 
41. 52 
1.57 
3.50 
1.07 
36. 84 
.44 
3.32 
12. 51 
.29 
30.98 
ALO, 
1.04 
Fe.,Oo 
4.88 
FeO 
2.01 
MffO 
38.44 
CaO 
22 
Na 2 
.40 
K 2 
.16 
H 2 at 100° 
.39 
H 2 above 100° 
20.43 
P 2 0, 
trace 
O 2 3 
.34 
NiO 
MnO 
.42 
S0 3 
.44 
99.56 
100. 70 
101. 06 
100. 15 
