48 The American Geologist. J"'>' i^o^- 
(a) French Creek. This variety is also fairly abundant at the 
Franconia Iron mine a mile and a half from Sugar Hill P. O., 
N. H., associated with epidote and hornblende (h). I also give 
an analysis (c) of the variety almandite containing consider- 
able manganese and found in large dodecahedral crystals with 
truncate edges at Bishop's ]\Iill, ]\Iiddletown, Delaware Co. 
Color: dark brown. 
A, 
nalysis of 
gar 
nets. 
a 
b 
c 
G. 
3-719 
3-991 
SiO. 
35-42 
35-65 
36.22 
ALO3 
8.51 
3-76 
24-58 
Fe^Oa 
21.04 
25-59 
FeO 
30-71 
MnO 
9.88 
1.82 
8.97 
CaO 
25-67 
32.96 
100.52 99 78 100.48 
IV. Genth's Undescribed Zeolite. 
Dr. F. A. Genth in his Mineralogy of Pennsylvania (p. 
no.) gives an analysis of an undescribed zeolite having an 
inclusion of calcite {b). Several years ago I obtained a small 
quantity of material, consisting of badly distorted crystals, 
but undoubtedly tetragonal and resembling the apophyllite 
from French Creek. Color : white, transparent ; lustre : vitre- 
ous. H. 4-4.5 ; Gr. 2.609. , B.B. easily fusible, becoming 
opaque, and giving alkaline reaction. Calcite not present. 
An analysis a afforded 
a b 
Si02 39-53 43-36 
AI2O3 26.38 28.78 
CaO 14.89 10.95 
Na^O .87 .68 
K2O 2 . 22 1 . 38 
H2O 16.59 15.52 
100.48 100.67 
It is evident that Dr. Genth's zeolite is dift'erent from the 
one vmder consideration, but until more and better developed 
crystals are obtained it is useless to ascribe it to any known 
species and still less so to assume that it is new. The material 
analyzed, however, was entirely ])ure. 
