Report of the Bureau of Mines of the Department of Internal Affairs of ...

xvi INTRODUCTORY TO Off. Doc.
Prices range from 70 cents to |2 pei- ton.
The reports were received from four coal mines which were producing
clay or sliale that is used in making front brick. The shale
from those mines is mined in connection with the coal, and add materially
to the output of the mine.
Tons produced from the four mines 90,837
Average price per ton, $0 43
Thickness of seam,
2 to G feet.
The bricks mad« from these shales after being burned are usually
of a beiiutiful butt" color, and in many cases sustain a greater weight
than granite. It has occurred to me that those who are interested
in good roads might be aided by studying the possibility of these
shales being used, especially where the native rocks are not suitable
for road ]»urjK>ses, for in those localities shale suitable for brick
usually abounds. It is a fact that the most refractory clays or shales
are usually found near No. 12 or the Pottsville conglomerate and
may be found in localities where the coal has been all canied away.
It is from this geological position that clay suitable for fire brick of
every description and quality is found; for rolling mills, glass furnaces,
bessemer, open liearth and crucible steel works, foundries,
malleable iron works, glass works and every purpose for which fire
bricks are used. The following is an analysis of clay taken from
near the conglomerate and below the seam of coal, and is divided
into three sections designated (1) hard clay, (2) under strata, and
(3) sand:
Hard clay.
Under strata.
Silica
Alumina
Lime
Magnesia
Piroxiile of iron
AlkalieB
Titannic acid
Undetermined matter and
Water of constitution
less
Total
45.75
39.14
trace
trace
1.34
2.05
0.36
n.39
60. 8C
28.18
1.34
1.48
0.20
8.02
Tiie hard clay is the base and by the use of it in conjunction with
the other clays the brick is produced suitable for the varied puri^ses
for which fire brick is used.
Tlun'e is no doubt that large areas wni th exploring for these clays
exist in localities whei'e it lias been gixcii no attention and wlici-e it
coiild be utilized witli jH-otit.
Deductions from Mine Inspectors'' Ke|)Oi'ts.
I'MisI ani liiacile dislrict inspector calls attention to the cause of
the huge peicentage of fatal accidents in his district, which he