32 ALASKAN MINERAL RESOURCES IN 1905. 
Three types of mineral deposits may be distinguished in this district, namely, fissures 
veins, fractured zones, and lodes along the contact of intrusive rocks. Of the first class tl 
Comet, Northern Bell, and Savage veins are the most important. Mining at these loealiti 
has shown usually solid bodies of quartz 2 to 10 feet in width and striking in a norther 
direction, with steep dips to the east. The diorite walls are ordinarily free and well define 
and often show the presence of soft gouge. Along the direction of the strike the quar 
veins gradually wedge out and the continuation of the fissures is defined by a chlorite schi^ 
evidently developed from the diorite by slipping along the fissure plane. In the veins tl 
gold occurs both native and associated with sulphides, and the larger portion of if can 1 
recovered by amalgamation. The values are not always uniformly distributed in the ledgj 
and often follow shoots or are segregated in pockets. 
Deposits of the second type are exposed at the Kensington and Eureka mines and a 
essentially fractured /ones in the diorite which have been filled with intersecting veinlets 
quartz, carrying sulphide minerals, the latter frequently penetrating the diorite itself. 
Deposits of the third type, which resemble the fractured zones of the second class, 0CC1 
either along the contact of the diorite and greenstone, as exposed at the Johnson lode, or i 
the diorite and slate, as at the Creek Hoy lode. At these localities the contact zone i-; pen 
t rated by many quartz veinlets and in or near these the gold values are found. 
The Comet mine, which was operated from IN!) I to 1001 , is one of the curliest locatioi 
in this area and has been the greatest gold producer. It belongs to the Berners Bay Minii 
and Milling Company and is located at 2,350 feet elevation, not far below t he divide bet wee 
Sherman and Johnson creeks. ' At 1 ,000 feet elevation a crosscut tunnel 1 ,875 feet in lengt 
has been driven tot lie ( omet vein, from which point an aerial t ram 5,000 feet long extenj 
to a 10-stamp mill on Sherman creek. At 2,600 feet elevation two parallel veins are expos* 
on l he surface, but only the latter, the foot-wall vein, has been mined in depth. It is a wel 
defined quartz-filled fissure, which varies from 2 to 8 feci in width in the upper levels, whi 
in I he lower levels masses of the count ry rock are included in the vein, thus forming a widi 
ore body of lower grade. 'Die cont inuat ion of this vein to the nort h is faulted and, « :ou<. 
its direct extension has not been found, it seems probable that the Northern Bell vein nu 
be t lie same, a- it- character and the values contained are identical. 
From the main level to the surface the ('omet vein has produced over 50,000 tons of or 
which yielded a total of about $ 100,000. From this ore 87 per cent of its gold contents wet 
recovered in bullion and 5 per cent in the concent rates. Future mining must be carried <; 
below the main level and may be hampered by the inflow of water along the fault plai 
which follows the gulch between this mine and the Northern Bell. 
The Northern Bell mine, the property of the Northern Bell Cold Mining Company, wi 
operated in L896 and 1S07 and produced during that time nearly 23,000 tons of ore, whic 
yielded 78 per cent of the gold values in bullion. The ore body, as already noted, resemble 1 
the Comet vein to the -out li. 
The Bear mine, the oldest of the group of claims belonging to the Berners Bay Mining an I 
Milling Company, has been opened at 1,340 feet elevation by a 1,100-foot tunnel, in whic 
two well-defined quartz veins are crosscut at points 300 and 550 feet from its mouth. Froj i 
drifts extending several hundred feet in each direction along these veins 5,500 tons of quart 
ore were mined during the years L895-1897. The ore was much lower in value than tin: 
from the Comet mine and only 02 per cent of the gold was recovered in bullion. 
During the years 1897 to 1900 the Kensington ore body, controlled by the Berners Ba 
Mining and Milling Company, was opened by extensive surface and shallow undergroiuj 
workings. It is situated at a point 2,900 feet above tide water, and from it nearly 12,00 
tons of ore are said to have been mined. The following distribution of values was reporte 
from the mill returns: Bullion 5 per cent, concentrates 62 per cent, and tailings 33 per cent 
This ore is totally unlike the Comet ore. and hence must be treated by different methodst 
prevent the great loss in the tailings. 
In 1904 a crosscut tunnel starting at 1,800 feet above sea level was completed, and at 
point 1,950 feet from its mouth undercuts the Kensington lode. The ore body where inlei 
