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of building the railway proved to be much greater than had been antici-
pated and as a result in 1919 the holdings of the Dolly Varden Mines
Company passed into the hands of the Taylor Engineering Company. At
that time 15 miles of the railway had been built. The Taylor Engineer-
ing Company then built the remaining 2 miles to the lower camp and
organized the Taylor Mining Company. The company built a two-bucket
tramway from the mine to bunkers at the lower camp and commenced
shipments of ore. Before the end of the year the company had shipped
6,709 tons of ore containing 424,000 ounces of silver. The Taylor Mining
Company carried on mining until 1921 when their operations finally
ceased. ‘Total shipments from the mine in the three years amounted to
36,609 tons of ore which yielded 1,304,409 ounces of silver.

The mineral deposit is a vein and from an elevation of 1,600 feet
above sea-level it strikes west to the top of a low, wooded mountain known
locally as Dolly Varden mountain. The rocks of the mountain are massive
and fragmental igneous rocks of the Hazelton group cut by diabase dykes.
Most of the rocks appear to be massive, are green to grey, and contain
many fragments of igneous rock. Associated purple and red rocks are
probably of a fragmental nature. The vein lies in grey or green rock for
most of its length, but for part of its course follows the contact between
grey or green rocks and purple rocks. The vein strikes west and dips north
70 degrees. It has been offset by a number of northerly striking faults
with horizontal offsets of 50 to 120 feet but with probably very little
vertical throw. There are also horizontal thrust faults and a few normal
faults.

The vein is 5 to 25 feet wide. Quartz makes up about 70 per cent
of the vein, pyrite is abundant, calcite and jasper are uncommon, barite
occurs but is common only in the deeper parts of the vein. Chalcopyrite,
galena, and sphalerite occur in small quantity. The valuable contents
consist of tetrahedrite, native silver, argentite, ruby silver, and pearceite.
Much of the siliceous vein matter mined was of a very dark shade.

Mining operations disclosed that the faulted segments of the vein
outcropping between elevations of 1,850 and 1,700 feet were ore shoots.
These were mined, as completely as faulted and broken ground would
permit, to depths of 100 to 240 feet, but were not mined to deepest economic
level. The hanging-wall of each ore-body was free from the ore, was not
altered by the ore solutions, and consisted of purple tuffs. The foot-wall
was grey to green rock altered by the introduction of sericite, quartz, and
pyrite, and in some places was mineralized with ore minerals so that the
position of the wall was determined by assay. It is probable that faulting
took place along the hanging-wall after the vein was formed. Farther up
the hill the vein continues as large as ever, but there no longer follows the
contact between the purple tuffs and the green massive rock and so far as
known does not contain any ore shoots.

The ore shoots consisted of the usual vein minerals but the silver
minerals were particularly plentiful. The writer believes that the rich
silver ore was of secondary origin and has presented evidence for this view.1
In a preceding section of this report the source of the deposits of the Dolly

1 Hanson, G.: Can. Inst. Min. and Met., Trans., vol. 25, pp. 212-224 (1922).
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