56 GEOLOGY OF MOOSE RIVER GOLD DLSTRICT — WOODMAN. 



age, knots of some light colored mineral. This is either calcite, 

 or quartz grains, or indeterminate masses looking like almost 

 decomposed felspar. 



Arsenopyrite is not found in slides of slate, to any extent, 

 but is present in those cut from quartzites ; and fails to show 

 stretching. Pyrite is abundant in both rocks. Usually it is 

 elongated with the cleavage ; but in some cases the crystalline 

 shape is unaltered, and in others it has a ramified margin and 

 cellular interior, because of having crystallized in the massive 

 form and adapted itself to its surroundings. This variety often 

 encloses bits of biotite and chlorite. Most of the cellular nature, 

 however, results from the presence of quartz grains. 



Cleavage and schistosity. — All the sediments are heavily 

 cleaved. The planes of fissility are parallel to the general 

 strike of the rocks ; and in highly inclined strata, or those in 

 which original division planes are poorly marked, cleavage is 

 readily mistaken for bedding. The quartzite is poorly cleaved 

 as a rule ; but near the surface, weathering has in many places 

 brought out the incipient fissility so as to give a tolerably good 

 sandstone slate. The pelite'.has taken the cleavage well ; but no 

 such perfection is reached as in roofing slate, for the necessary 

 uniformity of texture is wanting. In places even the slates 

 show little cleavage to the e^^e underground, but blasting brings 

 out the greater weakness along these planes, and the circulation 

 of shallow under- water has increased fissility near the surface to 

 a high degree. 



The cleavage is everywhere highly inclined, but often several 

 degrees from vertical. In the quarry at the center of area 75, 

 it strikes N. 80° W., and dips 79' to 80° S. On area 182, at the 

 exposure from which the " fossils " were taken, the direction is 

 N. 87° W., dip 52° S. At the west end of the quarry on area 

 131, where the Serpent lead was exposed in 1897, it lies N. 80° 

 W., with a dip 67° S. North of the district half a mile to a 

 mile, several observations show it to be nearly vertical. 



