clabke.] ANALYSES OF ROCKS, U. S. GEOLOGICAL SURVEY. 337 
SliATES AND SHALES. 
VERMONT. 
Samples A to I, inclusive, are described by T. Nelson Dale in 19th 
Ann,, Part, III. Analyses by W. F. Hillebrand, record Nos. 1567, 
1656. Rooting slates of Cambrian age. 
A. McCarty quarry, South Poultney. 
B. Unfading green, Eureka quarry, Poultney. 
C. Sea green, Griffith and Nathaniel quarry, South Poultney. 
D. Sea green, Rising and Nelson's quarry, Pawlet. 
E. Sea green, Brownell quarry, Pawlet. 
E. Black, American Black Slate Company, Benson. 
Si0 2 .. 
A1A- 
Fe 2 3 
FeO.. 
MgO. 
CaO_. 
H,0 at 100 c 
Ti0 2 
PA 
MnO 
BaO. 
bo 2 . 
FeS_, 
C ... 
61.63 
16. 33 
4.10 
2.71 
2. 92 
. 50 
1.26 
5.54 
.31 
3.24 
.68 
.16 
.09 
.06 
.41 
.04 
none 
99.98 
B. 
59.27 
18. 81 
1.12 
6.58. 
2.21 
.42 
1.88 
3. 75 
.32 
3. 98 
.99 
.11 
.13 
.05 
.21 
.15 
none 
99. 
62.37 
15.43 
1.34 
5.34 
3.14 
. 77 
1.14 
4.20 
.34 
3. 71 
.74 
.06 
.22 
.07 
.87 
.06 
trace 
99.80 
67.76 
14.12 
. 81 
4.71 
2.38 
.63 
1.39 
3.52 
.23 
2. 98 
.71 
.07 
.10 
.04 
.40 
.22 
none 
E. 
100. 07 
59. 84 
15. 02 
1.23 
4.73 
3.41 
2.20 
1.12 
4.48 
.41 
3.44 
.74 
.09 
.34 
.09 
2.98 
.05 
trace? 
100. 17 
59. 70 
16.98 
.52 
4.88 
3.23 
1.27 
1.35 
3. 77 
.30 
3. 82 
.79 
.16 
.16 
.08 
1.40 
1.18 
.46 
100.05 
All six contain traces of lithia, of sulphates, and of nickel or cobalt. 
Bull. 228—04 22 
