smith.] GOLD MINING IN CENTRAL WASHINGTON. 77 
creeks. The gravel deposits are from a few feet to 70 or 80 feet in 
thickness, and while red or yellow in color at the surface, the gravel 
is blue below. The upper portions of the gravel are also less easily 
worked, since induration of the gravel has followed the oxidation of 
the cementing material. 
While fine gold is found throughout the gravel deposits at some 
localities, most of the gold occurs close to bed rock and in channels 
other than those occupied by the present streams. Its marked char- 
acteristic is coarseness. Pieces several ounces in weight are common, 
while a number of nuggets weighing 20 ounces or more have been 
found, and one or more nuggets of about 50 ounces have been reported, 
the largest nugget of the district having a value of $1,100. These 
larger nuggets are usually well rounded, but on the tributary streams 
wire and leaf gold is found. The gold is not pure, containing consid- 
erable silver, which materially decreases its value. 
The bed rock, which belongs to the Swauk formation, of Eocene age, 
is usually of a nature to favor the collection of the gold. The 
inclined beds of hard shale form natural "riffles," and from the 
narrow crevices in the shale the best nuggets are often taken. The 
sandstone beds wear smooth, in which case the bed rock is apt to be 
barren. The old channels, both of Swauk Creek and of its tributaries, 
vary somewhat in position from the present course of the stream, but 
only within definite limits. The old valleys and the present valleys 
are coincident, but, within the wide terraced valleys of the present, 
older channels may be found, now on one side and now on the other. 
Thus, on Williams Creek and the lower portion of Boulder Creek, the 
old water course has been found to the south of the present channel of 
the stream, and is in other cases below the bed of the creek. On 
Swauk Creek the deposits worked are above the level of the stream, 
being essentially bench workings. Here hydraulic plants have been 
employed, but elsewhere the practice has been to drift on bed rock. 
While the endeavor is to follow the old channels, it is found that the 
" pay streak " can not be traced continuously. Ground that will yield 
to the cubic yard of gravel handled may lie next to ground that 
does not contain more than 50 cents to the cubic yard. In the last 
few years the operations in the Swauk Basin have been on a larger 
scale. Williams Creek has been dammed and methods have been 
devised to handle the tailings and bowlders on the lower courses of 
Swauk Creek, where the gradient of the valley is low. 
The source of the alluvial gold is readily seen to be the quartz veins 
known to occur in the immediate vicinity. These will be discussed 
in a following paragraph. The noticeable lack of rounding of much 
of the gold shows that it has not be<m transported far, and indeed the 
limited area of the Swauk drainage basin precludes any very distant 
source for the gold. It is only along the Swauk within a few miles of 
Liberty and on Williams Creek and its tributaries that gold has been 
