35

to 12 inches of clean sulphide, consisting mostly of finely banded galena
and jamesonite; near the top there is a band of 8 inches, mostly of zine
blende. These zones have good walls and are said to carry high silver
values; the showings are well worth further development and are excep-
tionally promising.

Assays by the British Columbia Bureau of Mines of samples from
Sunset group, are as follows:

Bright clean galena from a 4-inch stringer in mineralized shear zone:
gold, 0-02 ounce; silver, 140 ounces; lead, 72-5 per cent.

Across 5 feet of shear zone: silver, 49-8 ounces; lead, 24-2 per cent;
zinc, 5-2 per cent.

Picked ore from same zone as No. 2: gold, trace; silver, 86 ounces;
lead, 61-6 per cent; zine, 7-5 per cent.

Farther east in the other basins similar deposits are known, but the
above descriptions are typical.

Paragenesis of Ores. The paragenesis of the ores from this locality is
similar for all the deposits and is as follows.

Table of Paragenesis of the Ores on the North Side of Ninemile Mountain.

Fissuring of the country rock with the formation of veins and shear zones

Deposition of quartz with some calcite

Siderite

Arsenopyrite and pyrite

Zinc blende

Tetrahedrite \

Galena veining zinc blende

Jamesonite

Zinc blende is usually the most abundant metallic mineral, then jamesonite, and then galena;

there is considerable finely crystalline arsenopyrite, but not so much of the other minerals. Plate
XA shows the relationship of the jamesonite to the zine blende.

Discussion. The Ninemile ore consists only of the following minerals:
pyrite, arsenopyrite, zine blende, galena, jamesonite, and tetrahedrite, in a
gangue of quartz and calcite. The pyrite and arsenopyrite are distinctly
earlier than all the other minerals and are followed by zine blende and
tetrahedrite (jamesonite and galena). The calcite is earlier than the
metallic minerals and is commonly found thickly impregnated with needles
of jamesonite asin Plate XB. There does not appear to have been two
distinct periods of mineralization, but simply a gradual cooling of the
solutions as they precipitated their minerals in these veins.

It seems unwarranted that these properties should remain idle at a
time when lead and silver are in such demand. They could be reasonably
proved at no great expense and they are admirably situated for co-operative
handling of ore to a mill-site, say on the Shegunia river just below them;
this stream could also furnish all the power necessary for a large develop-
ment. At present there is a good wagon road from the railway at New
Hazelton to the properties, a distance of about 10 miles by road.

Properties on Fourmile Mountain.

Fourmile mountain is situated about 4 miles northeast of Hazelton,
just north of the Bulkley river, and is reached by a good wagon road. It
rises to 2,200 feet altitude, or 1,400 feet above the river, and has an almost
circular core of granodiorite which is about 4,000 feet in diameter. :

On the north, west, and south sides of this mountain usually in the