TAKU RIVER AREA.

Mineralogie Features—The mineralization of No. 1 and No. 2 zones is yery similar. It
differs, however, in form of distribution and in grade. Both zones are mineralized with very
fine-grained chalcopyrite, zinc-blende, pyrite, and some galena, in a dense quartz-calcite-barite
gangue. The chalcopyrite occurs intimately intermixed with pyrite, partly in fine-grained
massive development generally towards the centre of the zones, and partly in fine-grained lateral
dissemination gradually giving place to an intensifying fine-grained zince-blende dissemination.
The zinc-blende mineralization in turn gradually diminishes laterally in intensity to a compara-
tively barren sheared margin near the walls. The central chalcopyrite segregation seems to be
more generally confined to No. 1 zone, which is consequently perceptibly better in grade, where
developed, than No. 2 zone. No. 2 zone is decidedly low in grade where developed and shows a
tendency to greater widths, with a consequent tendency to dispersal of mineralization.

Ore-zones and Workings on Surface—No. 1 ore-zone has been traced on the surface by three
open-cuts from an eleyation of about 1,680 to 1,805 feet in a horizontal distance of 200 feet. In
these workings the zone shows an average width of about 20 feet, assaying: Gold, 0.1 oz. to the
ton; silver, 4.7 oz. to the ton; copper, 1.2 per cent.; zine, 10.1 per cent. This zone strikes
N. 45° B. and converges towards a dacite dyke striking N. 20° E., which lies easterly of it. At
elevation 1,825 feet, and about 60 feet northerly from the upper open-cut, the rhyolite on the
west side of the dacite dyke seems to plunge beneath the andesite and No. 1 zone abuts on the
dyke and undergoes a pinching. This condition continues towards the north. In this direction
the formation is a “tight” dense andesitie rock. The dacite dyke continues on to northward,
cutting the andesite, but a careful examination failed to reveal the continuation of either No. 1
or No. 2 ore-zones in this direction. It would seem that the fracturing and shearing, readily
transferred through the rhyolite, have diminished against the buffer of dacite in contact with
the tough andesite. :

At altitude 1,865 feet, No. 2 zone has been exposed on the surface for a length of about 30
feet, showing ore-widths of from 5 to 15 feet, assaying: Gold, 0.1 oz. to the ton; silver, 1.4 oz.
to the ton; copper, 2.7 per cent.; zine, 7.5 per cent. This zone strikes N. 20° E., has a general
steep westerly dip, and lies adjacent and parallel to the dacite dyke. Surface continuity towards
the north is affected adversely by the same conditions goyerning that of No. 1 zone. About
800 feet to the south of the open-euts on No. 2 zone, and at altitude 1,025 feet, a wide exposure
of pyritized rhyolite has been open-cutted. In places this shows massive fine-grained pyrite
similar to the development of that mineral in the upper cuts on No. 1 and No. 2 zones. Zine
and copper mineralization is not evident in these lower cuts. Further work is required to
definitely correlate these lower showings with either of the two zones. 3

Underground Development.—The ore-zones have been explored by A and B level tunnels at
altitudes 1,690 feet and 1,500 feet respectively. At the time of examination (September 5th)
about 1,400 feet of development had been completed in these two tunnels; 600 feet of this work
is crosscutting, of which 175 feet, or about 30 per cent., is lateral work in the ore-zones. Of the
800 feet of drifting, about 500 feet, or 62 per eent., is in ore of promising grade.

On A leyel about 160 feet of drifting and 22 feet of crosscutting is on No. 1 zone, westerly
of the dacite dyke, and about 170 feet of drifting and 56 feet of crosscutting is on No. 2 zone,
easterly of the dyke. No. 1 zone is indicated at this level, carrying fair mineralization. Its
width is indicated to average about 9.5 feet, but varying from 30 feet at the southerly end of the
drifting to 6 inches at the northerly end, where it enters the tough, dense andesite. If is inter-
esting to note that the pinching of No. 1 zone on A level occurs about 80 feet north of the vertical
projection of its surface pinching.

No. 2 zone is indicated on A level carrying only fair mineralization, a decidedly lower-grade
ore than No. 1 zone. Its width is indicated to vary from 6 to 24 feet, with an average of about
17 feet. At the time of examination the face of A level drift in No. 2 zone showed pronounced
fracturing and shearing, with a deyelopment of sericite and kaolin. Both zones show an erratic

but generally steep westerly dip on this level.

At the time of examination B level development was entirely on No. 1 zone. A continuation
of the crosscut for 125 feet in cherty rhyolite beyond the intersection of No. 1 zone had failed to
pick up No. 2 zone in that distance. Of the 700 feet of work completed on this level, 370 feet
is drifting and 68 feet is crosscutting on the zone. The work on No. 1 zone on this level shows
a decidedly better grade of ore than on A leyel. The chalcopyrite content in particular shows