264 
ANALYSES OF ROCKS, U. S. GEOLOGICAL SURVEY. 
[NO. 228. 
WASHINGTON. 
Rocks A to J, inclusive, from the Mount Stuart quadrangle, Kit- 
titas County. Collected by George Otis Smith, who furnishes the 
petrographic data. Analyses A, B, C, F, and G by H. N. Stokes, 
record No. 1836; D, E, H, and I by W. F. Hillebrand, record No. 1831 ; 
J by George Steiger, record No. 2040. 
A. Granodiorite, south slope of Mount Stuart. Tonalose. Contains 
plagioclase, orthoclase, hornblende, biotite, quartz, and magnetite. 
B. Granodiorite, ridge between Hardscrabble and Cascade creeks. 
Tonalose. Contains plagioclase, orthoclase, biotite, hornblende, quartz, 
magnetite, and apatite. 
C. Granodio rite-porphyry, dike 2 miles west of Mount Stuart. 
Tonalose. Contains plagioclase, biotite, hornblende, orthoclase, and 
quartz. 
D. Serpentine, Three Brothers. Derived from saxonite. Contains 
serpentine, bastite, magnetite, and pyrite. 
E. Metamorphic rock, head of Beverly Creek. Believed to be 
derived from an inclusion of limestone in the peridotite. 
Si0 2 
ALA 
Fe 2 3 
FeO 
MgO 
CaO 
Na 2 0. 
K 2 
H 2 Oat 110°... 
H 2 above 110 c 
Ti0 2 
PA 
Cr 2 3 
NiO 
MnO 
SrO 
BaO 
Li 2 
C0 2 
S 
FeS 2 " 
A. 
B. 
64. 04 
63. 37 
15 58 
15.90 
1.26 
1.41 
3.22 
3.18 
3.23 
3. 33 
4.51 
4. 63 
4.01 
4. 05 
2.22 
2.10 
.19 
. IS 
1.17 
1.16 
. 69 
.69 
.16 
.17 
none 
none 
none 
none 
trace 
trace 
trace 
none 
.11 
.06 
trace 
trace 
none 
none 
trace 
trace 
100. 39 
100. 23 
63. 78 
16.39 
1.12 
2. 76 
3. 27 
4.07 
3. 84 
2. 03 
.22 
1.82 
.44 
.11 
none 
none 
.05 
trace 
.08 
trace 
none 
trace 
99. 98 
39. 00 
1 . 75 
5. 16 
1.71 
38.00 
trace 
.10 
1.31 
12.43 
trace 
trace 
.47 
. 10 
.15 
none 
none 
none 
none 
03 
100. 21 
E. 
32.12 
.82 
2. 05 
3. 50 
26. 73 
1.81 
.06 
.43 
.98 
trace 
trace 
.27 
.08 
.14 
none 
none 
31.04 
100.03 
"Actual condition of sulphur not known. 
