132 CONTRIBUTIONS TO ECONOMIC GEOLOGY, 1902. [bull. 213. 
the small nodules inclosed in well-defined schistose structure show no 
trace of it internally. Quartz is often present in the ore, but barite, 
so common at Bully Hill, is absent in the Iron Mountain district. 
The ore bodies usually separate easily from the wall rock, and at 
many points there are considerable masses of sericite selvage, but 
none so large as in the Bully Hill mine. The ore bodies are cut by 
small transverse faults, and, as pointed out by Mr. Lewis T. Wright, 
the general manager of the Mountain Copper Company, the sides of 
the ore bodies are occasionally polished by movement since the ore 
was deposited. 
Balaklola and Shasta King. — Northeast of Iron Mountain, in the 
same district, there are many claims more or less extensively pros- 
pected, among which may be mentioned the Sugar Loaf, King Copper, 
Spread Eagle, and Balaklala; but it is not until Shasta King, on Squaw 
Creek, is reached that extensive activity is found. The Trinity 
Copper Company, Mr. A. H. Brown, general manager, controls the 
Shasta King, Uncle Sam, and numerous other claims in the neighbor- 
hood, and is cautiously developing them. The ores at the northern 
end of the district are in general not so rich as those of Iron Moun- 
tain and need to be handled under the most favorable conditions. 
SI last a King is north of and below Balaklala, which is on the oppo- 
site side of Squaw Creek, and it seems probable that their ore bodies 
lie in the same shear zone. The country rocks in both places may be 
most appropriately designated metarhyolite. At Balaklala a large 
pyritous bod}* of ore lies a short distance beneath the slope. It has 
the general strike of the district and dips to the northwest nearly par- 
allel to the slope. Although much gossan occurs in the region, the 
slopes are usually so steep that it has been removed, and the dark 
sulphides form a very thin layer between the gossan and the pyritous 
ore. 
In the Shasta King the ore body lies nearly flat and at its western 
end above is firmly united — "frozen" — to the country rock. This is 
exceptional in the copper region and even about the same ore body, 
for along its eastern border it has a well-defined selvage ranging from 
a mere film to a foot in thickness. 
Beyond Squaw Creek the Mammoth mine and the Summit, on Little 
Backbone Creek, are near the northern limit of the district. 
Detailed maps on a larger scale than that of the folio publication, 
which is only 2 miles to the inch, are now being made, preparatory to 
a special detailed study of these mining districts. 
