Location
The Georgetown district is in northwestern El Dorado County at the north end of the northeast segment of the Mother Lode belt. It extends from just north of Garden Valley north through Georgetown and the Georgia Slide area to the Middle Fork of the American River. It is both a lode- and placer-mining district.
History
Mining began here in 1849 by a party of placer miners from Oregon. The site was first known as Growlersburg, but was soon changed to Georgetown. It is reported to have been named for either George Ehrenhaft, who laid out the town, or George Phipps, a sailor-prospector. The placers were highly productive during the 1850s. The seam deposits at Georgia Slide were mined on a large scale by hydraulicking from 1853 to about 1895. There was some activIty during the early 1900s, and in the 1930s the Beebe and Alpine mines were worked on a fairly large scale. There has been minor prospecting and skin diving in the district since.
Geology
This district is in the northern end of the Mother Lode gold belt (see fig. 4). There is a two-mile wide north- and northwest-trending belt of Mariposa slate (Upper Jurassic) in the central portion of the district, with greenstone and green schist to the west and mica schist, slate, quartzite, amphibolite, and serpentine to the east. In places, especially at Georgia Slide, the bedrock is deeply weathered. Several patches of Tertiary gravel overlain by andesite are exposed on some hills in the northern part.
Ore Deposits
The ore deposits consist of thick zonettf mineralized schist and slate that contain numerous quartz veins and veinlets. Where deeply weathered the gold became concentrated and such deposits were worked by placer-mining methods. These are known as "seam" deposits. Below the weathered zone they were mined as lode deposits. The seam deposit at Georgia Slide was 1000 feet long and 500 feet wide. Usually the milling ore yielded from 1/7 to 1/5 ounce to the ton, but many high-grade pockets were encountered. In addition, there are several wide quartz veins containing finely disseminated free gold and pyrite. These veins contained ore shoots with stoping lengths of up to 500 feet. The Tertiary gravel patches have yielded gold.
Mines
Lode-seam: Alpine $500,000+, Alma, Barney, Beebe $2 million, California Jack, Cove Hill, Georgia Slide $6 million, Mamaluke, Mount Hope. Placer: Anderson, Bottle Hill, Cary, Cement Hill, Holmes, Jones Hill, Little Chief, Mulvey Point, Patterson, Rowe, Shoemaker, Tanksley, Trimble.
Bibliography
Clark, W. B., and Carlson, D. W., 1956, El Dorado County, Seam deposits and Georgetown area: California Jour. Mines and Geology, vol. 52, pp. 431 and 435-437.
Irelan, William, Jr., 1888, Alpine mine: California Min. Bur. Rept. 8, pp. 167-168.
Lindgren, Waldemar, and Turner, H. W., 1894, Placerville folio, California: U. S. Geol. Survey, Geol. Atlas of the U. S., folio 3, pp.
Lindgren, Waldemar, 1911, The Tertiary gravels of the Sierra Nevada: U.S. Geol. Survey Prof. Paper 73, pp. 108-169.
Logan, C. A., 1935, Mother Lode gold belt of California, Alpine, Beebe, and Georgia Slide mines: California Div. Mines Bull. 108, pp. 15-19 and 46.
Preston, E. B., 1893, Georgetown: California Min. Bur. Rept. 11, pp. 202-204.
