200  -F. A. Genth’s Contributions to Mineralogy. 
In tale slate probably belonging to the lower Silurian 
tion, associated with small octahedra of chromic iron, and 
liar mineral, resembling pyrosclerite and serpentine. The 
ses gave: . 
I IL. 
Ignition, - - - 0°82 
Chromle iron and quartz, - - 058 1:27 
Silicic acid, - - - 41°89 40:87 
Ferrous oxyd, = - - - 7°39 7°39 
Nickel oxyd, - . - 0°35 
. Magnesia, - —-- - 49°18 
Lime, - - - 0°06 
z net lilt og } traces 
as , 10021 
1 . 
sulting from be oxydation of the fides oxyd of the chrysolite. 
An analysis of the talc gave : 
a Water, ‘te ees 3 = - 0°34 
8 Silicic acid, —- : : 5 : ‘ - 6444 
a ina, - < ‘. = . 3 z - 0°48 
fe Ferrous oxyd, - . > : 9 ‘ +i ae 
: Nickel oxyd, | - me s : me ‘ - 033 
aS Magnesia, = = oe, 6 e : - 33:19 
2 
i Bf 
° 
i) 
for 
3 
Sz 
& 
BB. it extoliates 
