342 ANALYSES OF ROOKS, U. S. GEOLOGICAL SURVEY. [no. 228. 
PENNSYLVANIA. 
Slates from Lehigh and Berks counties, collected by T. N. Dale. 
Analyses by W. F. Hillebrand, record No. 2015. 
A. Black roofing slate, Washington vein, Hazel Dell quarry, north 
of Slatington. Sp. gr., 2.780, 21°. 
B. Black roofing slate, lower Franklin vein, old Franklin quarry, 
Slatington. Sp. gr., 2.783, 21°. ^ 
C. Black roofing slate, partly weathered, 1\ miles northwest of 
Waxatawny, Berks County. Dark variety. 
D. Like C, light variety. 
E. Weathered slate or "shale clay," one-half mile south of Fogels- 
ville. 
F. Like E, one-fourth mile from Guth Station, South Whitehall. 
A. 
B. 
C 
D. 
E. 
F. 
Si0 2 
56. 85 
15. 24 
1 5. 52 
2. 93 
4.24 
1 . 38 
3. 34 
.45 
undet. 
.84 
56. 38 
15.27 
1.67 
3. 23 
2. 84 
4.23 
1. 30 
::. 5i 
.77 
4.09 
.78 
trace? 
65. 56 
17.06 
1 4.19 
1.31 
.20 
.26 
3. 81 
J- 7.0!) 
.68 
68. 81 
16.44 
} 3 - u 
1.00 
.20 
.27 
4.32 
\ 5. 33 
. 77 
64. 50 
21.67 
1.09 
.18 
.20 
4.26 
| 5.65 
.85 
75. 77 
A1 2 3 - - - 
1 15. 30 
Fe 2 3 
FeO 
MgO - 
.81 
CaO 
.20 
Na 2 
K.,() 
trace 
2.85 
H 2 at 105° 
} 4. 69 
.36 
H 2 above 105° 
Ti0 2 
Zr< )., 
C0 2 
3. 58 
undet. 
3. 67 
.17 
none 
undet. 
.02 
none 
undet. 
p 2 o 5 - 
S 
undet, 
undet. 
o.,o, 
trace? 
undet. 
undet. 
undet. 
undet. 
1.72 
undet. 
trace? 
.09 
.08 
trace 
trace 
1.72 
.59 
Mn( ) 
BaO 
SrO 
Li 2 
Carbonaceous matter 
undet. 
undet. 
96.09 
100. 39 
100. 18 
100. 28 
100. 23 
99.98 
