WEIGHT AN 
WRIGHT. 
D ] DEVELOPMENTS IN SOUTHEASTERN ALASKA. 67 
The Cascade mine is located about 3£ miles west of Hollis. The 
ledge averages 2 feet in width and occurs as a tilling along a slipping 
plane in an altered basic eruptive rock. The chief development work 
consists in two tunnels 50 and 240 feet in length. The average value 
of the ledge has not been determined as yet. Visible gold is not 
uncommon. 
Gravina Island. — Miller's camp, the only prospect on the island 
which has been developed considerably, lies on the east side of Gravina 
Island, about 4 miles from Ketchikan. The formation consists largely 
of schists of various types with a northwesterly strike and a north- 
easterly dip. Certain bands of the series, 5 to 10 feet in width, are 
heavily mineralized with sulphides and constitute the ore bodies. Two 
of these bands have been discovered and prospected by shafts 50 feet 
deep. The gold value is reported to average $10 to $15 per ton. Sur- 
face improvements consist of a 5-stamp mill and mine house. In both 
shafts a highly altered basic intrusive dike has been found crosscutting 
the formation obliquely. The present outlook seems to warrant 
greater developments. 
The Hoadley Brothers' claims are located 2 miles north of Ketchikan 
md one-fourth mile from tidewater. The veins, although narrow, 
Dccur usually within a syenite dike, intrusive into the schist country 
rock. Two different sets of veins can be distinguished, the younger 
)f which is remarkable for its hig-h gold content. 
Dall Island. — On the east side of Dall Island, 2 miles from the south 
3nd, are the recently located Elk and Virginia groups of claims. These 
ire on four different quartz ledges, which vary from 5 to 30 feet in 
vidth and occur in both limestone and slate. The gold values are 
issociated with chalcopyrite and galena and ore assays varying from 
i>10 to $50 are reported. This property has been worked during the 
oast summer and the developments will continue throughout the 
ivinter. 
The Mount Vista group, in the central part of the east shore of Dall 
island, is located on a mineral belt in limestone and consists of numer- 
ous stringers and small masses of a tetrahedrite ore carrying high 
Values in gold and silver. This property is being opened by several 
|mall tunnels and the ore exposed is said to assay well. 
I Revillagigedo Island. — The "Sealevel" mine, located at the head of 
home Arm, was largely worked during 1900 and again in 1902-3, but 
ince the summer of 1903 all operations have ceased. Since Mr. A. H. 
Brooks's visit to this property in 1901 a 30-stamp mill has been erected 
nd a water-power plant built. Most of the ore between the surface 
nd the lower level has been stoped out and milled, and probably 
wing to the lack of sufficient ore to supply the 30-stamp mill and the 
ostly method of handling the ore, mining was discontinued. The ore 
