204 GRAVEL AND PLACER MINING IN ALASKA. [bull. 263. 
Creek, Klondike, for example, of the total weight of gravel handled, 1 
per cent of black sand, mostly magnetite, is caught with the gold in 
the clean-up. In American Creek, Alaska, the clean-ups are impeded 
by the presence of large quantities of barite pebbles. In the Fair- 
banks district red garnets and rutile, in some cases in quantity up to 
one-third of 1 per cent of the total material washed, are caught with 
the gold. In the Birch Creek district there is enough rutile in the 
auriferous sand to cause trouble in the clean-up. In Seward Penin- 
sula the magnetite is in comparatively small amount. Garnets occur 
in the creek diggings up to 5 pounds to the cubic yard of gravel. In 
the beach and so-called "tundra" gold sands of the coastal plain from 
3 per cent up to as high as 61 per cent of garnets occur/ 7 
The use of quicksilver in the northern operations of America is lim- 
ited. Even allowing for the extra expense and time consumed in the 
use and recovery of quicksilver, it is surprising that this important 
agency for saving fine go\d is not more generally employed. It has 
been shown that the proportion of fine gold in the interior fields is 
large. The neglect to use quicksilver in attempting to save such gold 
can be considered only as a penny-wise-pound-foolish polkyy. It is 
needless to say that in all of the appliances above suggested for the 
saving of fine gold the use of quicksilver is imperative. Carelessness 
in the use of quicksilver, however, may result in increasing rather than 
diminishing the loss of fine gold. According to Bowie/' float quick- 
silver containing microscopic gold particles has been taken from the 
surface of the water 20 miles from the place where the amalgam entered 
the stream. A single flask of quicksilver is ample for the needs of the 
average creek operation of the Klondike or interior Alaska, and even 
with wasteful handling would last a season. 
Whether quicksilver is used or not, it will be found advantageous to 
get the gold and amalgam as clean as possible on the floor of the sluices 
or tables before removing the valuable product. The comparatively 
small amount of heavy concentrates accompanying the creek gold of 
Seward Peninsula makes this possible in the frequent clean-ups of] 
the tailrace. Skillful manipulation will accomplish the same result 
in the interior except where excessive quantities of magnetite occur. 
In one case on Bonanza Creek, Klondike, the fine concentrates which 
could not be removed with the magnetite after drying were skillfully 
separated by dry-panning. 
Black sand or other concentrates have occasionally been found rich 
enough to pay for sacking and shipping to smelters after cleaning. 
Exaggerated reports of high assays in gold obtained from black sand 
frequently find credence. Nevertheless, whenever this concentrate 
a Brooks, A. H., Mendenhall, W. C, Collier, A. J., and Richardson, G. B., Reconnaissances i n the 
Cape Nome and Norton Bay regions, Alaska, in l'JOO, I), g. ftepV. Survey, 1901, p. 87. 
b A Practical Treatise on Hydraulic Mining in California, 1885, p. '244. 
