The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1913-10-09
small mines Ia the Prichard areas.
Relation of Ores to Small Fractures.

Relation Of Ores to Small Fractures.
The ores under discussion are liz
variably connected with small assures
in the Prichard rocks. The ore
shoots frequently are confined to the
places where the assures cut across
quartzite bands. The reason for this
Is the purely mechanical one that the
quartzite fractured better than the
states and gave rise to less gouge, as
pointed out by Mr.. Ransome. AS fis-
sures, they do not materially differ
from the fractures with which the ores
In higher formations are connected.
but in meteorological composition the
Prichard veins contrast rather strong
ly with the veins in the Burke and
Revett formations. Only one mine IN
the latter makes a zinc product, The
Morning mine near Mullan. am not
familiar with this mine, but Mr.. Ran
some describes the ore as containing
gaena, sphalerlte, pyrite and little
pyrrhotite in a gangue of siderlte. 5a-
rite, and quartz. The galena Is fine
grained, much of 1t of steel-like tax :
ture. The silver ratio is 3 to ounces
to 7 to per cent lead. This deposit,
therefore. is not of the Prichard type.
The nearest approach mineralogically,
that | have found in rocks higher than
the Prichard Is certin disseminated
zinc lead naturalization in the Revert
uuartzite in the Wardner district, In
which the zinc Is generally several
times as abundant as the lead and the
silver ratio is very low. The mode OF
occurrence, however is quite different
from the Prichard type. 1t is beyond
question that this type Is strictly con
fined to the Prichard formation. In
this formation 1t is widely distributed,
not in one continuous area, but In sep
arate areas on opposite sides OF the
great mining districts whose ores are
found in the Burke and Revett quartz
ties. There is an important group
east of Murray, another west of Sun
set peak, and a third in the Pine creek
basin. The type Is also represented In
the extensive Prichard area on both
sides of the South Fork of the Occur
d'Alene river near Kellogg and in the
Moon creek basin. 1t is, furthermore,
widely distributed in Prichard areas
beyond the Occur d'Alene district, in
northern Idaho and western Montana
nearly to British Columbia.
Mines and Prospects.
There are comparatively few pro-
ducing mines, but small prospects are
numerous. In the Burke and the Re-
vett quartzites, the ores are in larger
deposits connected with much small
er number Of assures, There are, in
the Occur d'Alene district, no mines
and relatively few prospects in the st.
Regis formation. In the Wallace there
is one mine, the Gold Hunter, near
Mullan, but extensive areas OF the
formation are without traces of lead
or zinc prospects. In this respect the
Wallace contrasts strongly with the
Prichard, although both formations
contain argillites There is nothing in
the structure to explain this contrast.
It leads me to the conviction that the
Prichard is much nearer, stratigraph-
ically, to the source of the minerals
than is the Wallace. The many small
deposits in the Prichard suggest that
they constitute the roots of the vein
system, that they combine upward in
to fewer and larger veins in the Burke
and Revett quartzites, and that few
of these veins survived as high as the
Wallace formation. This is purely fig
urative but conveys the idea that the
Prichard has been the source of the
lead, zinc and silver in the entire vein
system.
The Prichard type of naturalization
is not controlled by altitude. 1t ranges
from less than 1900 feet, near Kellogg,
to about $500 feet, at the Surprise
mine; 4400 feet at the Monarch mine,
1900 feet at the Terrible Edith mine,
and 500 feet at the Bear Top mine.
Other types of ore naturalization in
the district are known to range from
about 1900 feet in the Bunker Hill 4
C,,11ix,n,, ,,,tno ~ EDS0 foot at tha Ctan