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The high ash content of the Australia Creek lignite condemns it for
industrial purposes. The ash content undoubtedly yaries from point to
point and could be reduced considerably by careful sorting out of the shale.
The lignite should eventually prove useful as a local source of fuel. Two
seams of lignite 2 feet and 7 inches thick with 15 inches of clay between,

-erop out 200 feet down the creek from the tunnel. They correspond

stratigraphically with beds Nos. 25 and 22 in the section, page 17, which -

are 8 inches and 2 inches thick, respectively. Other seams, said to have
been exposed a hundred feet or so up the creek, were covered by debris at
the time of visit. Outcrops of lignites were reported on the east bank of
Fraser river 1 mile south and nearly 4 miles north of Australia creek,
but a search for these proved unsuccessful, owing perhaps to a combination
of slides and high water. No other outcrops of lignite are known in this
vicinity and no basis exists for believing that the outcrops mentioned on
the Fraser and that at the tunnel represent parts of a continuous bed of
lignite. The 3-foot 9-inch seam exposed in the tunnel probably underlies
an area of several acres, but its extent can become known only by develop-
ment work.

PERIDOT.

Peridots occur in a series of basalts on the summit of Timothy moun- ~

tain (Figure 2, locality 17, and Figure 13, locality 3, see also Plate XV).
Peridot is another name for the common, rock-forming mineral olivine,
Mg (Fe) SiO,. A dark green variety of this mineral is very much in vogue
as a cheap form of jewellery. According to one of the leading jewellers in
Canada peridot stones are used to give pleasing effects in combination with
other and more precious forms of jewellery and to harmonize with many
colours of wearing apparel. Although olivine is a common rock mineral,

- the dark green variety is rarely found in such form and quantity that it

can be profitably mined for commercial purposes. The stones are com-
monly cut in round, square, and oval shapes varying in size from 3 to 6
millimetres (4 to 4 inch). Cut stones of these sizes are sold at from 40
cents to $1.50, unmounted.

The basalts on Timothy mountain occur in two cone-shaped hills rising
for about 220 feet over the plateau-like floor of quartz diorite that forms the
summit of the mountain. Most of the peridot occurrences are on the north-
east and steepest side of the hills. The peridots occur in irregularly shaped
masses of red, brown, and green crystalline rock known as hypersthene
peridotite. These lie in a reddish-brown groundmass. The peridotite
masses generally have rounded corners, although there are many angular
fragments scattered through the basalt and one had the form of a brick
with banded layers. They vary in size from about ¢ inch to boulders 18
inches across. There are also boulders of grey quartz diorite in the basalt.
The masses are coarsely crystalline and are made up of olivine with a
lesser amount of pyroxene. The olivines are translucent, pale yellowish
ereen through dark green to black. In certain masses they are stained red
by iron oxide and this forms veinlets in the masses in places radiating out
into the basalt. The olivines vary in size from =4-inch to 4-inch and over
and have a conchoidal fracture and vitreous or glassy lustre. In the same

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