IGNEOUS AND CRYSTALLINE ROCKS. 
85 
WYOMING. 
Rocks studied by Whitman Cross. The Leucite Hills series is de- 
scribed in Amer. Jour. Sci., 4th ser., vol. 1, p. 115. Analysis J is by 
L. Gr. Eakins, record No. 1078. The others are by W. F. Hillebrand, 
one made in the Denver laboratory, and record Nos. 343, 355, 362, 368, 
403, 463, 1668, and 1082. 
A. Wyomingite, Boars Tusk, Leucite Hills. Contains phlogopite, 
leucite, diopside, and apatite. Sp. gr. 2.779, 13.5°. P. R. C. 567. 
B. Wyomingite, Fifteenmile Spring, Leucite Hills. Composition 
like A. Sp. gr. 2.627, 30°. P. R. C. 566. 
C. Portion of B soluble in 2.5 per cent nitric acid. 
D. Phlogopite from wyomingite. 
E. Madupite, Pilot Butte, Leucite Hills. Contains predominating 
diopside and phlogopite, with perofskite and magnetite, in a glassy base 
which has approximately the composition of leucite. Sp. gr. 2.857, 22°. 
P. R. C. 576. 
A. 
B. 
c. 
D. 
E. 
Si0 2 
50.23 
11.22 
3.34 
1.84 
7.09 
5.99 
1.37 
9.81 
.93 
1.72 
2.27 
1.89 
.10 
.03 
.05 
.24 
1.23 
trace 
.74 
.03 
.50 
53. 70 
11.16 
3.10 
1.21 
6.44 
3.46 
1.67 
11.16 
.80 
2.61 
1.92 
1.75 
.04 
none 
.04 
.19 
.62 
trace 
.06 
.03 
.44 
6.08 
.91 
1 . 50 
1.51 
2.13 
.28 
1.21 
(?) 
(?) 
.21 
1.54 
42. 56 
12.18 
2.73 
.90 " 
22.40 
.20 
.44 
10.70 
42.65 
9.14 
5. 13 
1.07 
10.89 
12.36 
.90 
7.99 
2.04 
2.18 
1.64 
1.52 
.07 
.11 
.12 
.33 
.89 
trace 
.58 
.03 
.47 
AlaO, 
Fe 2 3 
FeO 
MgO 
CaO 
Na 2 
K 2 
H 2 Oat 110° 
H 2 above 110° 
Ti0 2 
2.35 
2.09 
.06 
.73 
P 2 5 
Cr 2 3 
Di 2 3 , etc. a . 
MnO 
SrO 
.10 
.14 
trace 
1.00 
trace 
BaO 
Li 2 .. 
S0 3 .. 
.06 
.03 
CI 
F 
2.46 
Less O ............. 
100. 62 
.22 
100.40 
.19 
14.70 
100. 80 
1.03 
100. 11 
.20 
100. 40 
100. 21 
99.77 
99.91 
(^Probably contains other rare earths. 
