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Author: Admin | 2025-04-28
Individual operations on individual claims of only a few tens of acres. Two of the larger and more famous mines, the Polar Star and Southern Cross mines (Sec. 34,T16N, R10E) comprised 140 acres and were intermittently mined by hydraulic and drift methods. Along with several other smaller operations, these mines worked the gravels all the way to bedrock and are responsible for the large hydraulic workings immediately northwest of Dutch Flat. These workings, which comprise over a half-square mile, are known as the "Nichols Diggings.? Several other operations are responsible for the considerable bedrock exposures in the Blue Devil Diggings just west of town. DRIFT MINING Drift mining of the lower blue lead gravels at Dutch Flat commenced in 1856 and was followed in 1857 and later years by extensive hydraulic mining. Drift mining at Dutch Flat was far less extensive than in the more famous drift mining districts of the nearby Forest Hill Divide. Comment (Commodity): Commodity Info: Placer deposits: Placer gold dust to large nuggets. Placer gold was approximatly .970 fine. Lode deposits: Free-milling gold-bearing quartz veins. Comment (Commodity): Ore Materials: Native gold Comment (Commodity): Gangue Materials: Quartz and metamorphic gravels; quartz Comment (Geology): INTRODUCTION The Dutch Flat District is primarily a placer gold district having produced from thick sections of exposed Eocene auriferous channel gravels. Only minor production was obtained from a few small lode mines. The district also includes a few rather insignificant asbestos and chromite mines, which are not discussed herein. REGIONAL SETTING The northern Sierra Nevada is home to numerous placer and lode gold deposits. It includes the famous lode districts of Johnsville, Allegheny, Sierra City, Grass Valley, and Nevada City and the famous placer districts of La Porte, North Columbia, Cherokee, Michigan Bluff, and Forest Hill, and Dutch Flat. The geological and historical
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