CLARKE.] 
IGNEOUS AND CKYSTALLINE ROCKS. 
Ill 
2. SUNLIGHT INTRUSIVES. 
Descriptions, hitherto unpublished, supplied by Arnold Hague and 
T. A. Jaggar, jr. Analyses A, B, and C by W. F. Hillebrand, record 
No. 1801; D by H. N. Stokes, No. 1801. 
A. Quartz-syenite, Copper Creek Basin. Laurvikose. Contains 
biotite, hornblende, epidote, orthoclase, augite, titanite, magnetite, 
and apatite. Hornblende very pale in color. 
B. S3 r enite-porphyry, Sulphur Creek Basin. Lassenose. Contains 
oligoclase and biotite, in a groundmass of quartz and feldspar. 
C. Augite-syenite-porphyry, Copper Creek Basin. LauTvi/wne. 
Contains augite, biotite, orthoclase, a little hornblende, and quartz. 
D. Gabbro, southwest of Beams Hill, Sunlight Valley. Andose. 
Contains plagioclase, pyroxene, magnetite, apatite, and a little biotite. 
Si0 2 
A1A 
Fe,0, 
FeO.. 
MgO 
CaO 
Na 2 
K 2 
H 2 Oat 110° .. 
H 2 above 110 
Ti0 2 
PA 
to 2 
CrA 
VA 
NiO 
MnO 
SrO 
BaO 
Li 2 
co 2 
FeS, 
63.07 
17.47 
2.09 
1.38 
1.44 
2.27 
5.77 
4.59 
.25 
.43 
.38 
.18 
trace 
trace 
trace 
none 
.03 
.15 
.32 
trace? 
none 
.02 
99.84 
66.64 
16.22 
1.84 
1.06 
1.25 
2.41 
5.11 
3.86 
.52 
.55 
.29 
.16 
.01 
trace 
.01 
none 
trace 
.14 
.27 
none 
none 
trace? 
100. 34 
c. 
64.40 
16.90 
1.86 
1.37 
1.13 
2.60 
5.79 
4,56 
.16 
.39 
.23 
.21 
.02 
(?) 
(?) 
none 
.07 
.14 
.27 
trace 
none 
trace? 
53.57 
17.78 
3.19 
4.93 
4.36 
6.22 
4.04 
3.04 
.27 
.80 
.89 
.44 
none 
none 
.07 
.13 
.21 
trace 
none 
100. 10 
99.94 
