54 ALASKAN MINERAL RESOURCES IN 1906. 
with the axis of minor folding or wrinkling. The present underground 
developments are confined to the exploration of this ore body. 
From tide water to the mine a cable tramway 1 mile in length has 
been built. Just below the main tunnel a 20-stamp mill has been 
erected and was to be in operation by the end of 1906. For power 
purposes a 450-foot flume, with intake at 1,050 feet elevation on 
Nevada Creek, is connected by a pipe line 925 feet long with the com- 
pressor plant and mill at 750 feet elevation. 
The operations on the Red Diamond group at the head of Nevada 
Creek, which were started the year previous, were discontinued early in 
1906. On the Mammoth group and other adjacent properties assess- 
ment work alone was done. 
The properties of the Alaska Atlin Mining Company, the Yakamaw 
Mining Company, the Alaska Consolidated Mining Company, and 
others located on the island have been idle for several years, and no 
improvements of consequence have been made on them. 
GOLD (REEK MINES. 
The proposed mining improvements on the lode system which is 
strongly developed within the Gold Creek drainage and extends overr 
the Sheep Creek divide were not accomplished, and progress in actual! 
mining over the preceding year has been slight. 
Briefly, the deposits are of low-grade, free-milling ore and occur r 
within an 800-foot belt of black slate which has been intruded by 
numerous dikes 10 to 50 feet in width of a dark-brown, altered basic 
rock, probably a gabbro. Numerous quartz gash veins are preseJ 
within this belt, cutting both bedded and intrusive rocks, but are 
most plentiful near their contact. The auriferous sulphides, essen- 
tially pyrrhotite and pyrite, impregnate both the black slate and dike 
rocks, but the values arc principally in the quartz veins. The average 
value of the ore mined in a large way is very low, and this has to some 
extent discouraged the investments of capital necessary for theft 
economic development. It has, however, been demonstrated at both: 
the Ebner and Alaska-Juneau mines that the ore can be profit ably 
mined. This, with the undoubted persistence of mineralization and 
values in the lode system to a depth below which mining will likely go 
should tend to encourage mining operations. 
Operations at the Ebner mine were continuous during the year, anc j 
results similar to those of former years were attained. In the uppei 
tunnel the drifts were extended 350 feet, and in the lower tunnel 15( : 
feet of drifting was done. During the year the 15-stamp mill on the 
property was in continuous operation except for a few weeks in th( 
winter. The water power of Gold Creek at this point was sufficien 
to develop 125 horsepower throughout this period. 
