36 TIN DEPOSITS OF THE YORK REGION, ALASKA. [no. 229. 
stone; 5 per cent magnetite; other minerals, 5 per cent. The cassiterite occurs in 
grains and pebbles, from those microscopic in size to those half an inch in diameter; 
they have subrounded and rounded forms. In some cases there is a suggestion of 
pyramidal and prismatic crystal forms. The cassiterite varies in color from a light 
brown to a lustrous black. 
A second locality of this mineral was found on the Anikovik River, about half a 
mile below the mouth of Buhner Creek. Here the cassiterite was also found with 
the concentrates from the mining operations. One pebble of stream tin obtained 
from this locality was about 2 inches in diameter. 
It will be necessary to make a more detailed examination of this region to deter- 
mine where this mineral occurs in the bed rock. The facts obtained by the writer 
point toward the conclusion that its source was in the quartz and calcite veins in 
which the gold was found. No cassiterite was, however, found in this vein material. 
Since 1901 these workings have been abandoned by miners, neither 
gold or cassiterite having been found in paying quantities. On Ani- 
kovik River there are extensive gravel deposits, which may possibly 
be made to yield fair returns either in gold or tin if economically 
worked on an extensive scale by hydraulic methods. Sufficient water 
for this purpose can probably be obtained either from the head of 
Anikovik River or from Kanauguk River. 
LOCALITIES FROM WHICH STREAM TIN HAS BEEN REPORTED. 
It is reported by prospectors familiar with the Buck Creek deposits 
that some tin ore has been found in alluvial deposits on Baituk and 
Kigezruk creeks, flowing into Bering Sea; in Banner Creek, tributary 
to the Anikovik; several small streams flowing into Lopp Lagoon; 
Clara Creek, a tributary of Mint River; and in York Creek, a tribu- 
tary of Pinguk River, all in the York region. Stream tin has also 
been reported from all parts of Seward Peninsula where gold mining 
is in progress, but outside of the York region these reports have gen- 
erally been without foundation. Last summer, however, Mr. Hess 
obtained from a miner a specimen of stream tin said to have been 
found on Gold Bottom Creek, a tributary of Snake River, in the Nome 
district. If this find was genuine it indicates a wider distribution of 
the tin ore than has heretofore been supposed, and is the only case 
known in which stream tin has been found in the gold placers near 
Nome. There is probably not enough tin ore there to have economic 
value. 
The bed rock of Gold Bottom Creek consists of limestones and schists 
of the Nome series. 
SUMMARY OF ECONOMIC GEOLOGY. 
Tin ore in considerable quantities has been found in the York region 
at a number of widely separated localities, the extreme points known 
being 25 miles apart. While the existence of tin ore in sufficient 
quantities to be worked on a profitable scale has not yet been demon- 
strated because of the remoteness of the region, the inhospitable 
