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emanations from a ‘granitic’ fluid, with corresponding abstraction of lime.
No example of a transition within a single bed from tremolite-actinolite-
clinozoisite-garnet skarn into hornblende-plagioclase amphibolite was found
in the Wolverine complex, though such a gradation seems probable and
has been suggested (Barth, 1928). North of Blackpine Lake, skarn and
amphibolite are both interbedded with quartz-mica-feldspar gneiss, and
exist side by side for several hundred feet without noticeable change of
composition (See Figure 5). It is apparent that the amphibolite is not
merely a more highly metamorphosed phase of the skarn ; the two rock
types seem to represent somewhat different trends of alteration under
similar physico-chemical conditions.

Glimmerite

Near the edge of the southwest shoulder of the mountain overlooking
Blackpine Lake, and on a serrated aréte 3 miles north of this locality,
beds up to 3 feet thick composed almost entirely of biotite are intercalated
with the quartz-mica-feldspar gneisses. The biotite is in glistening black
scales up to 4 mm. in diameter, entirely similar to that found in the biotite-
bearing amphibolites. Accessory minerals are those found in the amphibo-
lites: hornblende, quartz, plagioclase, apatite, and sphene.

The glimmerite appears to be merely a phase of the amphibolite
extremely rich in biotite.

Pyrrhotite Skarn

In several places the skarns and amphibolites northeast of Blackpine
Lake are accompanied by deposits of iron sulphides, dominantly pyrrhotite,
with variable amounts of pyrite, chalcopyrite, and arsenopyrite. The
deposits range from thin seams of coarsely crystalline sulphides intercalated
with the skarns and amphibolites, to bodies up to 25 feet wide and 500 feet
long consisting of at least 40 per cent sulphide material. The largest of
these bodies, on which the Hope group of mineral claims was staked, is
described breifly on page 222, The characteristic association of iron
sulphide deposits with contact metamorphosed limestone, in relations that
appear directly related to metamorphism rather than to later hydrothermal
mineralization, has been noted by many workers (Knopf, 1933, p. 538).
Goldschmidt (1911, p. 211) found that in such deposits the iron sulphides
were usually partly older and partly younger than the skarn silicate
minerals. In the Wolverine complex rocks, the pyrrhotite appears to have
formed essentially contemporaneously with the silicate minerals, before the
conclusion of intrusive action, for dykes of alaskite crossing bands of
pyrrhotite-rich skarn show no evidence of mineralization.

Granodiorite

The most conspicuous feature of the Wolverine complex rocks north-
east of Blackpine Lake is a body of granodiorite about 5 square miles in
area exposed on the slopes overlooking the lake. Another body about 3
Square mile in area outcrops on the north side of the north peak of the
massif northeast of the lake, and smaller bodies of similar material are
found on the crest of a ridge 7% miles south of Chase Mountain. For the

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