IGNEOUS AND CRYSTALLINE ROCKS. 
167 
F. Andesito, PringleHili. Pulaskose. Contains plagioclase, ortho- 
clase, quartz, biotite, augite, magnetite, and apatite, with sometimes a 
little hornblende. Sp. gr., 2.651, 17.8°. Record No. 1124. P. R. C. 
528. 
Gr. Pringle andesite, dike. Laurvikose. Like F, but often contains 
sphene. Sp. gr., 2.690, 28°. P. R. C. 527. 
H. Bunker andesite, Lookout Mountain. Akerose. Contains pla- 
gioclase, orthoclase, augite, biotite, hornblende, quartz, magnetite, 
and apatite. Sp. gr., 2.699, 34°. Record No. 1091. 
I. Altered Bunker andesite, Robinson Plateau. Toscanose. Biotite 
gone, magnetite altered to limonite, feldspars not much attacked. 
Record No. 1124. Sp. gr., 2.580, 19.7°. 
J. Much-decomposed Banker andesite, ridge near Knickbocker Hill. 
Liparose. Augite, hornblende, and biotite all replaced by decompo- 
sition products, plagioclase much muscovitized. Record No. 1124. 
P. R. C. 592. 
Si0 2 .. 
A1A- 
Fe 2 3 
FeO.. 
MgO . 
CaO.. 
Na 2 0. 
K 2 0.. 
H 2 0.. 
Ti0 2 . 
PA- 
MnO 
CO, . . 
58.94 
17. 19 
2.63 
1.98 
1.52 
4.45 
4.20 
3. 90 
4.53 
.27 
.23 
.10 
99.94 
G. 
63. 49 
18.40 
2.44 
1.09 
.66 
2.30 
5.70 
4.62 
1.04 
trace 
trace 
.16 
trace 
99. 90 
ir. 
57. 01 
18.41 
3.69 
2.36 
2.34 
4.29 
4.95 
3.72 
2.29 
.27 
.42 
.21 
99.96 
I. 
63.88 
19.96 
2.21 
.57 
.58 
2.03 
4.19 i 
3.88 | 
2.63 
trace 
67.13 
18.41 
.45 
.07 
.44 
.55 
4.17 
5.28 
2.98 
.30 
trace 
trace 
99.93 
