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Encyclopedia Dubuque

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Affiliated with the Local History Network of the State Historical Society of Iowa, and the Iowa Museum Association.




DUBUQUE AND BRECKENRIDGE MINING COMPANY

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Breckenridge, looking West, circa 1880s. Mines on Iowa Hill (extreme right) used hydraulic techniques that severely damaged the environment. Photo courtesy: Summit Daily/Rick Hague, September 18, 2016. Photo reduction: Larry Hoelscher

DUBUQUE AND BRECKENRIDGE MINING COMPANY. In 1859 Summit County as part of the Pikes Peak gold rush. Iowa Gulch, located on the northern edge of Breckenridge, was like many other sites of gold mining. Mines began as small-scale, manual, one-man operations to larger-scale, equipment-intense operations with corporate funding of the large-scale operations. In succeeding decades, nearly all of the techniques used in placer mining, — pan, rocker, long tom, sluice box, giant, booming, shafting, and bank blasting — occurred on Iowa Hill. (1) Formed in 1882, the Dubuque and Breckenridge Mining Company owned land two miles from Breckenridge, Colorado. The vein of ore was eighteen inches thick and assayed at $90 per ton. Most of the stock in the mine was owned by residents of Dubuque. (2)

Miners organized mining districts to handle claims and settle disputes. Iowa Gulch, part of the Quartz Mountain mining district, held many claims, each extending 100 to 200 feet up and down the gulch and running from bank to bank.

The sheer cliffs of Iowa Gulch were created by an early mining technique called booming. Head gates released water held in reservoirs and ponds at the top of Iowa Hill. As the water rushed down the hillside over bluffs of loose sediments and soils tons of rock, soil and vegetation were carried into sluice boxes lined with wooden riffles that captured the gold. The use of "rockers" and "long toms" produced yields of $3 per day per man; booming recovered an average of $25 per day per man.

Miners realized by the late 1870s that booming could not break apart gold-bearing gravels bound tightly with clay. This led to the use of high-pressure nozzles called monitors or giants. The technique had been developed in California in the 1850s. The monitors moving side to side, up and down, and were able to swivel 360 degrees. In operation they delivered tremendous water pressure to the hillsides, washing down the gold-bearing material.

In 1905, the Banner Placer Mining Company, which then owned 500 acres on Iowa Hill, completed a 15-acre reservoir system to store water for the monitors. Automatic gates released water from the reservoir every few minutes, 24 hours a day. Over 2,000 feet of 22-inch steel-riveted pipe carried the water to 4-foot-wide sluices.

As late as 1915, the Summit County Journal reported that several men worked the Banner placer with satisfactory results. In 1918, workers found grains of platinum in the sluice boxes. A new, but unsuccessful, search for wealth began. (3)

The Colorado Mine Directory of 1879-1910 indicated activity for a Dubuque mine and the Dubuque Mining Company.

  Individual            Mine                 Mining Company              County                     Year
  
   S.S. Benne         Dubuque                                            Clear Creek                1879
   John C. Easley                                                        Clear Creek                1879
   W. W. Kirby                        Dubuque Mining & Tunnel Company    Clear Creek                1910
   W. G. Wakefield    Dubuque                                            Clear Creek                1879
   J. A. Wright                       Dubuque Mining & Tunnel Company    Clear Creek                1910      

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Source:

1. Mather, Sandie, "History: Mining in Iowa Gulch," Online: https://www.summitdaily.com/explore-summit/history-mining-in-iowa-gulch-in-breckenridge/

2. "Dubuque Latest Enterprise," The Daily Herald, July 22, 1882, p. 4

3. Mather

2. Colorado Mine Directory, Online:https://history.denverlibrary.org/sites/history/files/CO1879-1910mineDirect.pdf