Brush and Dana—Fuairfield County Minerals. 115 
over occurs in minute scales distributed through the massive 
eosphorite and giving it a green color, and is sometimes imbed- 
ded in the rhodochrosite. Minute tabular crystals are rare; they 
are observed implanted upon the gangue, and also scattered 
through the reddingite. In general aspect the mineral resembles 
some varieties of chlorite though very unlike in its brittleness. 
It has perfect basal cleavage. ‘The hardness is 85-4, and 
results. 
Dickinsonite crystallizes in the MONOCLINIC SYSTEM. The 
axial ratio and obliquity were obtained from the following 
n 
a gles :— 
Plane angle of the base=120° 0” 
cad, 001A 100, — 61° 30’ 
cam OO1A301, = 42°30’ 
The axial ratio is :— 
c (vert.) b a Q 
0°6917 0°5773 1:0000 B=61° 3” 
For the unit prism (not observed), 
InI = 66° 36’, and 113° 24’ 
The observed planes are as follows :— 
% ce, O, 001 m1, 10 
a, i-%, 100. SSR BBE 
j b, i% 010. a, -3-i, 30] 
‘The adjoining figure shows all of these planes except the’ 
clinopinacoid, which was only once observed. 
. illowing are the most important angles, measured and 
ulated : : 
