98

“This is a stoneware clay suitable for the manufacture cf pottery, crocks,
jars, teapots, etc. It would require some experimental work to fit the bodies
with suitable glazes, but it is probable that the usual Bristol and slip glazes used
for stoneware articles would answer.

“Some 3-inch, round, hollow tile, was made on a hand press, and sent to a
commercial sewer-pipe plant for a salt-glazing test.

“Salt-Glazing Test. The results of the salt-glaze tests on this clay show
that the glaze cannot be successfully applied at cone 3, as that temperature is too
low. The body showed no sign of vitrification, being still porous and rather
soft.

“Tt would require a temperature in the kiln of at least cone 5, or better,
at cone 6, to produce a glaze on this clay. It will then show a glaze equal to
number 315, but of lighter colour. The commercial kiln in which the tests were
made did not give a higher temperature than cone 3, hence it was impossible
to complete the test on this clay...... gO 123

“ Laboratory Nos. 319 and 820, are from the point near which the southerly
boundary of the Murphy bituminous-sand claim meets the east shore of the Atha-
baska river. Owing to slide and talus, the thickness of the clay would not readily
be accurately .determined, but appears to be quite 20 feet. At the points from
which the samples were taken the overburden appears to consist of from 10 to 20
feet of low-grade bituminous sand. What appear to be extensions of the same
bed reappear along the river at intervals for one-third of a mile to the
south of the point where samples were secured.

“Laboratory No. 319. A light grey, highly plastic, and smooth elay, with
good working properties. It must be dried slowly, being liable to check if dried
too fast. The drying shrinkage is 5-5 per cent.

“The following results were obtained on burning:

Cone Fire shrinkage Absorption Colour
Jo Jo
010 0 :. ee salmon
06 ‘0 10 ‘4
03 0°6 8 buff
h 1°3! 6 ee
5 2°0 5 grey
172 40 - vitrified ss
17 fused

“This is a typical stoneware clay, suitable for the manufacture of all classes
of stoneware articles, and pottery.

“Tt is not a fire-clay, but may be suficiently refractory for stove linings,
boiler-setting blocks, or other purposes where extremely high temperatures would
not be used.

“This is one of the best clays of the series; it closely resembles No. 317,
which is almost as good. It is not so refractory as No. 190, which stands up at
the highest temperature of any of these clays.”

Tests have been made of shales and clays occurring along the line of the
Grand Trunk Pacific railway in the vicinity of coal seams west of Edmonton and
some of these have been found suitable for common brick, fireproofing, and field
drain tile. The results of the tests are published by the Geological Survey,
Ottawa, in memoirs written by Heinrich Ries and J oseph Keele.

Ries says that “one of the most promising areas in which to prospect for
shales to be used in the manufacture of clay products is in the J asper Park region.

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