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Plagioclase, microcline and quartz are the predominating minerals, while biotite, titanite, epidote, apatite, zircon and garnet are present in smaller quantities. There is also a small amount of hematite, pyroxene and sericite. The rock, which is of a granitic composition, contains numerous crystallites and has been subjected to considerable strain and crushing, which has resulted in foliation.
The bent and metamorphosed condition of the calcite shows the shearing and crushing which the rock has undergone. 11 Phyllite same location as No. 9. A dark red, finely laminated rock consisting chiefly of decomposed biotite and feldspar, occasional quartz grains and sericite and much iron oxide.
The rock has probably been derived by dynamic metamorphism, from a coarse igneous rock like a gabbro. 7 Epidotic Sericitic Schist. Washkagama Lake. A fine grained compact gray rock, of aggregate structure, consisting chiefly of quartz, plagioclase and biotite, and the alteration products epidote and sericite.
10 Schistose Limestone Same location as No. 9. A white rock having a peculiar mottled appearance due to the inclusions of decomposing biotite which project from the surrounding mass of calcite. There is some sericite present, also magnetite, resulting from the decomposition of the biotite.
In the hand specimen it is an apparently pure orthoclase but in the thin section small scattered quartz grains are observed; as well as the alteration products, Kaolin and sericite. The minerals at contact are quartz, biotite, magnetite and hornblende. Both the quartz and orthoclase contain dust inclusions and crystallites, while the evidences of shearing and crushing are abundant.
The strain to which the rock has been subjected has resulted in a very fine lamination, and it is considerably weathered. 9 Calcarous Sericite Schist. Seven Miles East of Seal Lake. A dark compact rock, in which calcite and sericite predominate. Quartz is less plentiful. The results of shearing and pressure are very prominent and bring out the foliation, even in the calcite.
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