338 
ANALYSES OF ROCKS, U. S. GEOLOGICAL SURVEY. 
I NO. 228, 
(i. Unfading green, Valley Slate Company'* quarry, Poult new 
II. Mottled, purple and green, Eureka quarry, Poultney. 
I. Purple, 1 mile south of Hydeville, in Castleton. 
Si0 2 
A1 2 3 
Fe 2 3 
FeO .... 
MgO 
CaO 
Na 2 
K 2 
H 2 OatllO°... 
H 2 above 110 c 
Ti0 2 
PA 
MnO 
BaO 
C0 2 
FeS, 
F 
N, as NIL, .... 
59. 
18. 
1. 
6. 
2. 
1. 
3. 
4. 05 
1.02 
.10 
.07 
.05 
. 39 
.13 
.08 
. 03 
LOO. 26 
All three contain traces of lithia, nickel, and chlorine, and possibly of zirconia; in 
G and II traces of strontia. but none in 1. 
