69

Sample 1. Semi-refractory. A white, residual clay. Washing and
screening through 80-mesh sieve yields 50 per cent of plastic clay resembling ~
stoneware clay. This burns to a light grey, hard body. The crude clay, —
eround to pass a 16-mesh screen, has low plasticity but is easily moulded,
burns to a dark grey, hard body at cone 5 (1230 degrees C.). Total shrink-
age at cone 5, 8 per cent, absorption at same temperature 6 per cent.
Washed clay fuses at cone 15 (1430 degrees C.) and crude clay at cone 18
(1490 degrees C.). ;

Sample 2. A No. 8 fire-clay. A white and pink residual clay. Plas-
ticity low. Burns to a hard, buff body at cone 5 with total shrinkage 11
per cent and absorption 11 per cent. Twenty-five per cent of the crude is
clay. |
Sample 3. No. 1 fire-clay or kaolin. White and pink residual clay.
Ground to pass 16-mesh sieve. Plasticity low. All particles do not slake,
hence granular when wetted. Burns to a cream-coloured body at cone
5 with total shrinkage 15 and absorption 17 per cent. Portion ground to
pass an 80-mesh sieve; plasticity good, clay smooth when wetted. Floor
‘ tile burnt to cone 5 slightly off white colour and not vitrified. Clay makes ;
a good casting slip when poured into plaster moulds, but needs addition’
of potter’s flint because of high shrinkage. Clay not affected when heated
to cone 30 (1730 degrees C.), hence highly refractory.

Sample 4. Semi-refractory clay. Light buff, residual clay. Ground
to pass 150-mesh screen; plasticity fair but short in texture. Burns to
drab grey vitrified body at cone 5 with total shrinkage of 14 per cent.
Fuses to slag at cone 17. Resembles 2. !

Mr. Keele remarks on the results as follows: ‘These tests show that
the deposit is uneven in quality, that the clay-forming processes are not
completed, as plasticity is generally low and fluxing impurities are cather
high in certain portions. The clays of this deposit as a whole might be
worked for the manufacture of a low grade of firebeick, or as a mixture with
a more plastic clay for making sewer-pipe. If the material was crushed
and washed it would yield a certain amount of fine clay which could be used
in the manufacture of stoneware goods, but the yield of washed clay would
probably be too small to repay that operation. As the material is not
fine-grained and is not white either in the raw or burned state it cannot be
classed as a commercial kaolin or china clay.” |

There is another deposit about one-half mile or so along the slope to
the south, which the writer was unable to visit.

Baker Creek Canyon.

Samples 5 and 6 are from Baker Creek canyon opposite the village of
Quesnel. Sample 5 is from the base of a number of rock pillars on the north
side of Baker Creek canyon about 34 miles above its mouth (Figure 12,
locality 8). These pillars are partly changed to clay. The rocks are
erey to buff quartzites and argillites of Cache Creek age, with occasional
beds of black argillites. All of these rocks are exceedingly fine-grained and
quartzose. They have been much crumpled and folded. They are accom-
panied in varying amount by grey and cream-coloured clays that have been
formed by alteration of the hard rocks. A number of pillars on the steep
sides of the canyon, some of them over 100 feet in height, extend for a
distante of 400 or 500 feet. The upper clay masses are about 300 feet in

»