90 Microscopical Character of the Ore. — Adams. 
The examination of the "kernels" therefore shows that they are 
composed of a considerably crushed and altered granite, probably 
belonging to the class of hornblende granites. 
The Ordinary Granite — The grey granite which constitutes the mass 
of the rock and encloses the kernels, in the hand specimen shows no per- 
ceptible foliation and is impregnated with pyrite and quartz, the latter 
occurring also in the form of little veins traversing the rock in various 
directions. The quantity of these minerals present however varies 
considerably in the diflferent specimens. When examined under the 
microscope the rock is found to be composed of orthoclase, plagioclase, 
quartz, calcite, pyrite, with in some cases a very small amount of 
titaniferous iron ore and of some zeolite. Hornblende, chlorite, 
epidote and the other accessory minerals above mentioned were not 
found in any of the sections. 
As in the case of the "kernels" the rock exhibits a very distinct 
cataclastic structure, induced apparently by crushing, but the crush- 
ing has gone much further in some cases than in others. Both 
feldspars are more or less decomposed and show mechanical deforma- 
tion, the twin lines of the plagioclase being often bent and the crystals 
fractured and faulted transversely, and often presenting an appear- 
ance of having been shoved into one another. The individuals of both 
feldspars are usually surrounded by borders of broken grains from 
which arms of similar broken material frequently extend into the 
unbroken grains. In many other cases when the feldspars are exam- 
ined between crossed Nicols they can be seen to be in the act of fall- 
ing apart into a number of grains similar to those constituting the 
above mentioned borders. The orthoclase is present in larger amount 
than the plagioclase but as in the case of the "kernels" the latter 
mineral is as a general rule rather better crystallized than the former. 
Whether any of the quartz was an original constituent is a question 
which it is impossible to determine. A large amount of this mineral 
however is always present and most of it is of secondary origin, occur- 
ring in the rock in veins or in irregularly shaped masses. Small veins 
are found in all the specimens and are often seen sending off lateral 
arms into the rock. The quartz is clear and colorless and often con- 
tains lines of minute cavities. It is usually in large individuals, 
which although occasionally, especially in the narrow portions of the 
veins, show an uneven extinction, generally extinguish simultaneously 
over their whole extent. A considerable length of the vein is often 
composed of a single individual. The edges of the veins against the 
rock are well defined and the component grains come together along 
sharp lines without any of the interstitial broken material. Calcite 
often occurs associated with the quartz sometimes filling a portion 
of the same vein. In some cases it even preponderates over the 
quartz, forming the principal constituent of the vein. The quartz 
with its associated calcite is also seen in some sections in irregularly 
shaped masses, which, though pretty sharply defined against the 
more or less decomposed rock, at other times occur so that it is impos- 
