222 
ANALYSES OF ROCKS, U. S. GEOLOGICAL SURVEY. 
[NO. 228. 
J. Dolerite, Mount Ingalls. Ilessose. Described by Turner in 14th 
Ann., p. -441. Contains plagioelase, augite, hypersthene, magnetite^ 
and a few olivines. Analysis by W. F. Hillebrand, record No. 1273. 
P. R. C. 739. 
K. Dolerite, Mount Ingalls. Ilessose. Also in 14th Ann., p. 411. 
Like J, but with scarcely any olivine. Analysis by Hillebrand, record 
No. 1432. P. R. C. 740. 
L. Basalt, 4 miles southeast of Mount Ingalls. Andose. Also in 
14th Ann., p. 441. Contains plagioelase, olivine, augite, and mag- 
netite. Anal} sis by Hillebrand, record No. 1273. 
M. Olivine-basalt, 1£ miles from Franklin Hill. Ilessose. Contains 
plagioelase, augite, partly altered olivine, magnetite, and probably 
some glass. Description supplied by Turner. Analysis by George 
Steiger, record No. 1590. P. R. C. 755. 
N. Serpentine, Greenville. Described by Diller in Bull. 150, p. 372. 
Besides serpentine, the rock contains some magnetite and less chromite, 
with remnants of the pyroxene from which the serpentine was in great 
part derived. Analysis by W. H. Melville, record No. 1346. P. R. C. 
145. 
SiO, 
Fe 2 3 
FeO 
MgO 
CaO 
Na 2 
K 2 
H 2 Oat 100° .., 
H 2 above 100 c 
Ti0 2 
PA 
MnO 
SrO 
BaO 
Li 2 
Chromite 
J. 
53.91 
17.95 
2.23 
4.80 
5. 52 
10.40 
2.90 
1.34 
.20 
.20 
.52 
.21 
.10 
trace 
.05 
trace 
100. 31 
52.81 
16 60 
2.66 
6.13 
6. 12 
10. 14 
2.79 
1.05 
.38 
.54 
.84 
.23 
undet. 
trace 
.03 
trace 
L. 
50.56 
14.71 
3.54 
8.90 
4.07 
7.58 
2.94 
2.10 
1.06 
1.12 
1.71 
1.14 
.13 
trace? 
.25 
trace? 
M. 
100.32 ! 99.81 
51.21 
17.59 
4.71 
4.42 
7.12 
10. 36 
2.49 
.91 
.58 
1.07 
.31 
.09 
trace 
none 
none 
100. 
x. 
39. 14 
2.08 
4.27 
2.04 
39.84 
trace 
12.70! 
.1: 
100. V 
