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provisionally placed at the contact between known Takla group rocks on
the west and underlying rocks of pre-Takla age on the east. The Jupiter
mineral deposits are exposed near the bottom of the gorge at the junction
of Lay Creek with a small tributary stream locally known as Berry Creek.
The rocks in the gorge have been considerably altered: the andesites and
tuffs to smooth, shiny, chloritic and serpentinized rocks, and much of the
argillite to soft, flaky, graphitic material. A small body of blocky, less
friable, porphyritic rock of andesitic or dioritic composition, exposed near
the portal of the ‘main adit’ and encountered in some of the underground
workings, may be intrusive.

Two distinct types of mineral deposits are recognized on the property.
One is represented by a brecciated fault zone, striking north and dipping
steeply west, cemented by white quartz and cream-coloured calcite, which
contains much graphitic material and is sparingly mineralized with pyrite.
This fault zone has been called ‘vein No. 2’ by the owners. The other type
of mineral deposit is represented by well-defined fissure veins striking
northeast and northwest, consisting of quartz and calcite heavily mineral-
ized with sphalerite, tetrahedrite, galena, and minor chalcopyrite, covellite,
and pyrrhotite. The two largest of these veins, which strike northeast and
lie to the west and east of the ‘vein No. 2’ fault zone, have been named
vein No. 1 and vein No. 3 respectively.

Exploratory work has consisted of hydraulic stripping the steep slopes
of Berry Creek gulch, and of driving two adits, one on each side of the
ereek. The surface workings are now completely sloughed, but it is under-
stood that the mineral deposits were well exposed within an area of 250
by 140 feet.

The ‘main adit’ is driven into the west bank of Berry Creek about 50
feet above the level of Lay Creek. It consists of a drift, 795 feet long, on
the mineralized, brecciated fault zone (vein No. 2) and a total of 813 feet
of branch workings that explored subsidiary fault zones and the fissure
veins (See Figure 16). Vein matter in the fault zone followed by the drift
is very lensy. Pyrite is the sole metallic mineral noted, and occurs in part
very sparingly disseminated through quartz, in part somewhat more abund-
antly disseminated through the brecciated altered wall-rocks, but for the
most part as thin stringers and seams with calcite forming a matrix to the
fault-zone breccia. The fault zone contains much graphitic material;
lens-like bodies up to 4 feet wide, consisting almost entirely of soft, impalp-
able, carbonaceous matter, were noted. The best mineralized section
observed was about 100 feet long and in most places less than 2 feet wide.
Samples from this fault zone, taken by the owners, are reported (Lay, p. 21)
to have yielded 0-31 ounce to 7:18 ounces of gold a ton across widths of
2 to 12 inches. A grab sample taken by the writer in 1946 assayed: gold,
0-135 ounce a ton; silver, 4-75 ounces a ton; copper, 0-08 per cent; and
zinc, 0-60 per cent. Microscopic examination of specimens from this
deposit has shown no gold; it may be that the pyrite itself is auriferous.

The sphalerite-tetrahedrite-galena deposits, represented by vein No. 1,
vein No. 3, and several smaller veins, have a maximum observed width of
1 foot. Vein No. 1 has been followed by a drift for 105 feet, and vein
No. 3, on the opposite side of the ‘vein No. 2’ fault zone, for 60 feet. The
very close similarity in width, attitude, and mineralogy of veins No. 1 and