30 
ANALYSES OF ROCKS, U. S. GEOLOGICAL SURVEY. 
[BULL. 168. 
I. Peridotite, Belchertown. Contains hornblende, pyroxene, biotite, 
olivine, and magnetite. Analysis by L. G. Eakins, record No. 1326. 
J. Massive, coarse, altered diabase, Leverett. Contains saussuritic 
feldspar with black hornblende. Analysis by Eakins, record No. 1325. 
K. Tonalite, South Leverett. Dark green, chloritic. Contains red- 
dish feldspar, dark hornblende, and a network of dark-green epidotic 
quartz veins. Analysis by Eakins, record No. 1326. 
L. Biotite-granite, Moore's quarry, Florence. Very feldspathic. 
Quartz rare, with fluid inclusions. Feldspar mostly triclinic. ortho- 
clase and microcline present in small quantities. Little muscovite, 
some rutile. Analysis by Eakins, record No. 1414. 
Si0 2 . 
A1A 
FeA 
FeO. 
MgO 
CaO. 
Na 2 
K 2 0. 
H 2 0. 
Ti0 2 . 
P 2 5 
Cr 2 3 
MnO 
BaO. 
C0 2 . 
48.63 
5. 32 
2.91 
3.90 
21.79 
13.04 
.34 
.23 
2.81 
.47 
.21 
.36 
.12 
trace 
trace 
100. 13 
51.56 
14.82 
4.30 
7.21 
7.36 
7.09 
4.21 
.17 
1.47 
1.97 
.09 
trace 
trace 
100. 25 
55. 51 
16.51 
1.68 
4.57 
6.73 
6.73 
3.19 
2.46 
1.53 
.91 
.17 
11 
02 
100. 12 
L. 
73. 27 
15. 51 
.33 
1. 14 
.15 
2.74 
4.79 
1.66 
.68 
.10 
trace 
trace 
100. 37 
