CIRCLE PRECINCT. 191 
The gold-placer deposits vary so greatly as to dimensions that few 
reneral statements can be made. In fact, the width and the thick- 
less of the pay streak vary according to the cost of extracting it. For 
ftxample, if values of $2 to the cubic yard are the lowest that can be 
■profitably mined, as is probably the case with present usage in mining 
throughout most of the district, it puts a limitation on the dimensions 
If the pay streak quite different from what it would be if the costs were 
leduced to $1 per cubic yard. It is therefore very difficult to make 
Iny broad statement relative to the pay streak. 
I Throughout the gold-bearing region the alluvium can be said to be 
luriferous, inasmuch as it usually carries enough colors of gold to be 
lound by the ordinary methods of panning. On the other hand, the 
pay streaks as now mined (i. e., with a probable minimum value of $2 
lo the cubic yard) are confined to certain creeks and to certain chan- 
nels in the creek floor or on the benches. With these limitations it is 
probably fair to state that the pay streaks do not average more than 
ho or 50 feet wide through the district, though on some creeks, notably 
pn Mastodon, a width of over 200 feet has been mined at a profit. 
JProbably few single pay streaks are traceable for more than 1,000 or 
;]2,000 feet, though a succession of them may give practically a con- 
Itinuous zone of placers for several miles. 
The same limitations must be placed on any statement in regard to 
thickness. Gold may be distributed through the entire thickness of 
gravels, but appears to be more commonly concentrated in the 2 or 3 
feet next to bed rock. It is usually found to a varying depth in the 
weathered bedrock. In general it appears to be true that where the 
gravels are well rounded the gold is more uniformly distributed than 
where the material is angular, but in the first case the values per cubic 
yard are likely to be less. 
Most of the rich pay streaks have a lenticular form, with their longer 
axes parallel to the trend of the stream valley. The pay streak may 
be straight or may wind from one side of the valley to the other. It 
is more likely to be straight in the broader valleys than in the smaller 
ones. If the valley is asymmetrical, the pay streak may be crowded 
to the steep wall by the talus which comes down the gentle slope. 
The talus may also bury an older channel. 
In distribution the gold follows the same general law as the gravel, 
being coarsest at the points farthest upstream and gradually becom- 
ing finer downstream. The several exceptions to the rule noted only 
prove that the gold has in some places a very local source, being prob- 
ably derived from mineralized zones which cross the drainage courses. 
The average value of the gold of the Birch Creek basin, as reported 
by operators, is $17.73 per ounce, the Eagle gold being the purest and 
Dead wood the most impure. 
Prindle has described the various creeks in detail, and it will not be 
