CLARKE.] 
IGNEOUS AND CRYSTALLINE ROCKS. 
59 
4. MISCELLANEOUS ROCKS. 
A. Typical diabase, Rocky Ridge. Auvergnose. Analyzed for J. S. 
Diller, but not described. Analysis by E, A. Schneider, record No. 
1370. 
B. Ottrelite-phyllite rock, Liberty, Frederick County. Analyzed 
for G. H. Williams, but not described. 
C. Chloritoid separated from B. Analyses B and C by L. G. Eakins, 
record No. 1349. 
D. Quartz-schist, Shoemaker quarry, near Stevenson Station, Green 
Spring Valley. Described by Bayley in Bull. 150, p. 302. Contains 
quartz, muscovite, occasional tourmalines, microcline, zircon, and iron 
stains. Analysis by Schneider, No. 1370. P. R. C. 119. 
E. Mica separated from D. Analysis by Schneider, No. 1377. 
p.. 
E. 
Si0 2 
A1 2 3 
Fe 2 3 
FeO 
MgO 
CaO 
Na 2 
K 2 
H 2 at 100° . . . 
H 2 above 100° 
Ti0 2 
MnO 
Li 2 
F ... 
51.68 
15. 87 
1.46 
8.43 
7.84 
11.08 
1.86 
.34 
.16 
.15 
.72 
.12 
.15 
34. 92 
32. 31 
10.21 
8.46 
1.13 
.36 
2.12 
1.87 
5.29 
3. 37 
.23 
trace 
23. 40 
39.31 
5.14 
21.94 
2.18 
trace 
.20 
.20 
6.81 
1.19 
trace 
trace 
91. 65 
1.59 
3. 57 
.21 
.17 
none 
.07 
Lit:; 
.60 
.13 
none 
trace 
44.93 
29.81 
6.10 
1.16 
.50 
10.28 
1.38 
4.88 
1.05 
trace 
trace 
.22 
99.86 
100. 27 
100.37 
99. 5)2 
100. 31 
