Great Falls tribune. [volume] (Great Falls, Mont.) 1887-1890, 1888-01-14
DUSKY DIAMONDS.
PENNSYLVANIA RIVAL IN THE EX-
TENT OF IT'S COAL FIELDS.
When Developed Their Output Will
Equal in Quantity and Quality That
of Amy Section of the Union
Sand Cou1ee to the Front.


of the most competent experts of the
day. It is now tacitly admitted that the
deposit belongs to the Dakota group No.
1, of the early cretaceous period, and
though the character of the coal is essen
TALLY bitumenous, it still belongs to the
great liquitie belt of Montana, Wy
om1ng and the more southerly territories.
This is proved by the fossils contained in
the various horizons of the field, which
are identical in character, species and
genera with those found elsewhere in the
great liquitic belt.
The past two years have seen great
| impetus given to the exploration OF the
Sand Coulee coal field, so that now for
| over large area the thickness of the coal
vein, as well as its dip, are very well un-
derstood. This has been done, not only
by means of tunnels, but also by borings
on an elaborate scale which revealed the
wealth of the interior of the plateaus.
Much of this development has been due
to the energy of the Montana Central
railroad, which, since its advent in the
coulee, has increasingly labored to de-
termine the quantity and quality of the
COAL The results of these endeavors
may be easily guessed at when we con-
slider that this company has now nearly
| Is miles of railroad completed in the
coulee to give access to the coal mines;
this, tco only being beginning of the
vast developments which will be made
the coming year, and give employment to
an army of miners.
Not wishing to draw any invidious
comparisons with other coal fields, may
still say with justice, that for quality,
quantity and accessibility this coal field
is excelled by none in this part of the
northwest, and is decidedly superior to
the majority.
The coal vein has regular thickness
of from six to nine feet clear coal be-
tween the two principal shale bands, and
this is the part which will be worked
extensively. True there are mines where
the vein has the abnormal thickness Of
ID to 90 feet, but this will be found to be
local. The principal seam, mentioned
above, contains a band of steam coal,
which, by its density, as we'll as the large
amount of fixed carbon, will form an
admirable fuel for the Manitoba and
Montana Central railroads. The balance
of the seam contains thick horizon Of
coking coal, which by practical tests
has yielded coke bright, firm, and por-
Gus, good structure, and clear metallic
ring. In the supplying of
FUEL FOR IRON FURNACES,
this is an important factor, as the strength
of the coke will be able to Withstand the
weight OF superintendent strata Of iron
ores and limestone.
In the main body of the Sand Coulee
coal field the primary conditions under
which the coal was deposited were excep-
tionally favorable, resulting in superior
| quality of coal, greater thickness of vein,
and reader facilities for mining. In
common with the sister coal-fields viz:
Belt and Smith river, the coal must orig
inally have been lake-like deposit
formed from the deposition of decayed
roots of aquatic plants. Before being
| compressed by huge bodies Of sand this
, deposit must have been of enormous
) thickness In a subsequent era the con
r tour of the field was altered in level by
: local disturbances, probably originating
1 in the Belt mountains.
l In connection with the coal vein, at an
average distance below of from 40 to 60
feet are found two bands of carbonate OF
| iron, very similar to the grey band OF the
, east The upper stratum of ironstone va
) ries from feet to as high as feet and is
, richly impregnated with the metal Tests
show that phosphorus is non -exlstant, or
nearly so; lime is present in small
amount, and thus we have an ore that is
, Of the best description for the manufac-
:. ture of iron or steel This bed of iron
stone is unlimited in extent, and is easy
of acess everywhere in Sand Coulee. A
!: stratum of grey clay separates this band
of ironstone from the one below which is
} about 10 feet distant. This lower band is
3 about feet in thickness, and identical in
character with the other one.
REMARKABLE GEOLOGICAL FEATURE
of the Sand Coulee coal field is, that al
though the coal measures themselves
? | are Of the cretaceous age, the base of them
, rests conformably upon the earbonlferous
limestone, signifying either that this lime
ttone was dry land during the oeons OF
time intervening between the two depos-
its, or that tremendous erasion of rocks
has occurred in that interval. This car
boniferous limestone occurs in unlimited
quantities in Sand Coulee, and by practI-
cal proof furnishes fine article for mer-
/ chantable lime.
In some portions of the coal field, the
lime, iron and coal can be observed in the
same hill, all easy CT access and of good
quality. Truly this marvellous combina-
ton Of materials required by man, and
especially in a vicinity where they will be
SO much required for various purposes.
In this article have refrained from de-
scribing the various mines in detail, as
they have been before described in the
Tribune. need only say that they still