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Slide of the old stamp mill, circa 1950s

Date
1950 to 1959
Description
The old stamp mill, location unknown. A stamp mill (or stamp battery or stamping mill) is a type of mill machine that crushes material by pounding rather than grinding, either for further processing or for extraction of metallic ores. Breaking material down is a type of unit operation. A stamp mill consists of a set of heavy steel (iron-shod wood in some cases) stamps, loosely held vertically in a frame, in which the stamps can slide up and down. They are lifted by cams on a horizontal rotating shaft. On modern mills, the cam is arranged to lift the stamp from the side, so that it causes the stamp to rotate. This evens the wear on the shoe at the foot of the stamp. As the cam moves from under the stamp, the stamp falls onto the ore below, crushing the rock, and the lifting process is repeated at the next pass of the cam. Each one frame and stamp set is sometimes called a "battery" or, confusingly, a "stamp" and mills are sometimes categorized by how many stamps they have, i.e. a "10 stamp mill" has 10 sets. They usually are arranged linearly, but when a mill is enlarged, a new line of them may be constructed rather than extending the line. Abandoned mill sites (as documented by industrial archaeologists) will usually have linear rows of foundation sets as their most prominent visible feature as the overall apparatus can exceed 20 feet in height, requiring large foundations. Stamps are usually arranged in sets of five. Some ore processing applications used large quantities of water so some stamp mills are located near natural or artificial bodies of water. For example, the Redridge Steel Dam was built to supply stamp mills with process water.

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Correspondence, E.H. Syphus to H.E. George

Date
1902-01-26
Description
This folder is from the "Correspondence" file of the Sadie and Hampton George Papers (MS-00434)

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Correspondence, Levi Syphus to Mr. A. E. Green and Mr. David Naylor Jr.

Date
1926-02-11
Description
This folder is from the "Correspondence" file of the Sadie and Hampton George Papers (MS-00434)

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Correspondence, Levi Syphus to Willard George

Date
1940-05-20
Description
This folder is from the "Correspondence" file of the Sadie and Hampton George Papers (MS-00434)

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Report from U.S. Geological Survey on pottery

Date
1912
Description
This folder is from "Maps and Assorted Documents" file of the Sadie and Hampton George Papers (MS-00434)

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Information on the composition of magnesite

Date
1874 to 1944
Description
This folder is from "Maps and Assorted Documents" file of the Sadie and Hampton George Papers (MS-00434)

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Photograph of a mine, 1890-1920

Date
1890 to 1920
Description
Unidentified individual works in a mine shaft.

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Correspondence, Levi Syphus to Sadie George

Date
1928-10-18
Description
This folder is from the "Correspondence" file of the Sadie and Hampton George Papers (MS-00434)

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Correspondence, Levi Syphus to Sadie George

Date
1929-04
Description
This folder is from the "Correspondence" file of the Sadie and Hampton George Papers (MS-00434)

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Notarized placer claim

Date
1901-04-29
Description
This folder is from "Legal Records" file of the Sadie and Hampton George Papers (MS-00434)

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