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VICINITY OF OROVILLE AND CHEROKEE FLAT. 487 
The low gravels near Oroville I did not examine with sufficient care to justify any extended 
report upon them. Along the banks of Feather River, for a distance of perhaps 400 feet below 
the bridge, bed-rock is now exposed to view. Below that point a few spurs of high bed-rock 
used to be seen in the bed of the river before the accumulations of the tailings. Bed-rock 
is also seen in the eastern part of the city. With these exceptions, it may be said that the 
whole river-bottom is filled with gravel. On the right bank of the river the gravel of Thomp- 
son’s Flat, extending back to the base of South Table Mountain, has been worked near the 
river at a great many places. The faces of the banks are visible from the opposite side of 
the river for a long distance. At the claim of Mr. O. P. Powers the banks are from fifty to 
sixty feet high. The lack of a good outlet makes it difficult to work these banks to advan- 
tage. The gravel contains but little quartz; its mass is made up of crystalline rocks, similar 
to those seen in the bed of the present streams. The gold is said to be very fine, and to be 
pretty evenly distributed through the gravel from top to bottom. No bed-rock is to be seen 
in the mine at Powers’s claim. The gravel also carries an unusual quantity of black sand. 
It seems probable that this came from the wear of the neighboring basalt. On the left bank 
of the river, in the city of Oroville, the gravel mine of Mr. J. B. Hewitt is the most extensive. 
Owing to the lack of grade, the banks farthest from the river can now be worked to a depth 
of only twenty or twenty-five feet. The gold is fine and scaly, and uniformly distributed. It has 
a fineness of .947 on the average. The gravels of the vicinity of Oroville have recently attracted 
considerable attention, for the reason that Mr. Edison has found that they contain a larger per- 
centage of platinum than is usual in these deposits. At the present time Major McLaughlin, an 
associate of Mr. Edison, is engaged in erecting works at Oroville, with the expectation_of saving 
the platinum, and at the same time recovering a large part of the gold which is carried off with the 
black sands. 
