CLARKE.] 
IGNEOUS AND CRYSTALLINE ROCKS. 
79 
The following- rocks, with one exception, are described by Clements 
in his portion of Mon. XXXVI: 
E. Mica-diorite, sec. 28, T. 42 N., R. 32 W., southeast of Crystal 
Falls. Shos/ionose. Contains plagioclase (andesine), orthoclase, quartz, 
biotite, hornblende, and titaniferous magnetite. Analysis by Stokes, 
record No. 1721. 
F. Hornblende-gabbro, sec. 29, T. 42 N., R. 31 W., west bank Michi- 
gamme River, east of Crystal Falls. Hessose. Contains labradorite, 
hornblende, and iron oxide, with subordinate pyroxene, biotite, and 
orthoclase. Analysis by George Steiger, record No. 1712. 
G. Bronzite-norite, same locality as F. Auvergnose. Contains 
bronzite, hornblende, and labradorite. Analysis by Steiger, record 
No. 1712. 
H. Wehrlite, sec. 29, T. 42 N., R. 31 W., on Michigamme River, 
east of Crystal Falls. Eossweinose. Contains hornblende, pyroxene, 
olivine, biotite, and iron oxide. Analysis by Stokes, record No. 1721. 
I. Picrite-porphyry, sec. 27, T. 44 N., R. 32 W., northwest of Mans- 
field. Principal minerals serpentine, amphibole, chlorite, ilmenite, 
all but the last being secondary. Analysis by Stokes, record No. 
1721. 
E. 
F. 
G. 
H. 
I. 
Si0 2 
58. 51 
16. 32 
2.11 
4.43 
:;. 7.°, 
3.92 
3.11 
4.08 
.23 
2. 00 
.72 
. 30 
49.80 
19.96 
6. 32 
.49 
7.05 
11. 33 
2.22 
.61 
.13 
1.71 
.79 
.07 
48. 23 
18. 26 
1.26 
6.10 
10.84 
9.39 
1.34 
.73 
.26 
2.00 
1.00 
.07 
44. 99 
5.91 
3.42 
8.30 
21.02 
9.79 
.91 
.74 
.63 
:;. 19 
.97 
.05 
. 25 
trace 
37. 36 
ALA 
4.76 
Fe 2 3 
6. 61 
FeO : 
6.12 
MgO 
31. 11 
CaO 
1.19 
Na 2 
trace 
K 2 
trace 
H 2 at 1 10° 
.65 
H 2 above 110° 
10.37 
Ti0 2 
.79 
P 2 0, 
.06 
Cr,0, 
.62 
MnO 
trace 
trace 
NiO 
.04 
co 2 
none 
. 15 
.43 
trace? 
none 
99.46 
100. 63 
99.91 
99.17 
99.68 
Ba, Sr, CI, F, S, S0 3 not looked for. 
