The Eagle mine was a lode gold mine located on 47 acres one and one-half miles north of Grizzly Flat. A three foot wide vein was worked for gold, while another deposit 150 feet long and up to 6 feet wide contained appreciable amounts of auriferous (gold containing) pyrite, galena (lead ore) and sphalerite (zinc ore). The mine was developed by a 780-foot drift adit and a 240-foot shaft.
A second Eagle lode gold mine was located on 18 acres just east of Greenwood.
A third Eagle mine was a placer gold mine on 122 acres about one and one-half miles northwest of Omo Ranch on a tributary of the Middle Fork of the Cosumnes River.
A fourth Eagle mine was a placer gold mine on 40 acres one mile south of Georgetown.
The Eagle Bird mine was a placer mine three miles southeast of Placerville.
The Eagle King mine was a lode gold mine near the first Eagle Mine mentioned, one-half mine further north of Grizzly Flat. A gold bearing quartz vein three to four feet wide, like at the Eagle Mine, contained not only free gold but also appreciable amounts of auriferous pyrite, galena and sphalerite. The mine was active from 1894-1896 and developed by a 1200-foot drift adit and a 60-foot winze 200 feet from the portal. The ore was treated in a ten-stamp mill.
The Earl Quartz mine was a lode gold mine one mile west of Grizzly Flat.
The Earl Fruit Co. mine was a placer mine located near the South Fork of the American River and is now under Folsom Lake. The Earl Fruit Co. was a major fruit packing company with a large facility in Placerville at one time.
The Eastern Buckeye placer mine was located on 31 acres one mile southeast of Placerville.
The Echo claim was on the Mother lode one and one-half miles northeast of Diamond Springs.
The Eden Consolidated Quartz mine was on 31 acres of the Mother Lode, one and one-half miles south of Placerville.
The Edner mine was located on 87 acres one and one-half miles southeast of Omo Ranch, in the very southern part of El Dorado County. A one and one-half foot wide vein of gold bearing quartz was mined in 1896 and developed by an 150-foot adit and a fifty foot shaft. There was also an Edner Placer mine near or at the same location. It is listed as being 87 acres in size.
The Edward Crocker claim was on 140 acres three miles west of Rescue. Given its location, it was probably a lode gold claim.
The E. E. Copper mine was four miles southeast of El Dorado. In addition to copper, gold and silver were mined at this location by means of an 85-foot vertical shaft, 200 feet of drifts and 100 and 300-foot adits.
The Elain, Washington and Witmer claims were a group of claims on 39 acres, one mile east of Omo Ranch.
The Elder placer mine was on the South Fork of the American River, four miles east of Salmon Falls.
There have been a number of mines in the county with the name El Dorado. The Church mine, two miles south of the town of El Dorado, was once known as the El Dorado. There was also an El Dorado lode gold mine in Spanish Dry Diggings, just south of the Middle Fork of the American River and and El Dorado placer gold claim on Otter Creek, six miles northeast of Georgetown.
The El Dorado Big Tunnel Company was a mining company that, in the 1890’s, operated a mine at Big Canyon, two miles north of Placerville. Later the mine was purchased by the Gentle Annie Mining Company. Ultimately, this mine, under the name of the Gentle Annie, would be consolidated with the Bell, Hall Consolidated, Lucky Star, Lyon and New Era claims under the name of the River Hill Group. The El Dorado Big Tunnel Company also operated a slate mine near Chili Bar around 1894.
One mile south of Garden Valley was the El Dorado (Roosevelt) Copper mine. Located on the Mother Lode gold belt, the mine was originally worked for gold in the 1860’s. During WWII some copper was discovered and mined. Because of the need for copper for the war effort, during the period 1944 – 45 the U.S. Bureau of Mines used a diamond drill to create eleven exploratory holes, aggregating a total of 1613 feet. Eight of these holes indicated the deposit to be a series of narrow, intermittent lenses of copper ore in an area about 600 feet in length and several hundred feet deep. The ore contained from five to more than ten percent copper, as much as one and one-half percent zinc, one ounce per ton of silver and traces of nickel and gold. The mine was developed by a 100-foot inclined shaft, a 173-foot adit, driven as a crosscut for forty-six feet and a drift for 127 feet, which connects with the shaft at the fifty foot level, 128 feet in from the adit portal. On the 100 foot level, there are drifts extending thirty-five feet to the north and ten feet to the south.
The El Dorado County Road Department (later Public Works and now Department of Transportation) has operated several stone quarries over the years. From these deposits of decomposed granite they have taken material for “road metal” (surfacing material), fill material and sand for increasing vehicle traction on icy roads. Presently they operate only one sand quarry on Sandridge Road, near the townsite of Somerset. But, at one time there were county operated sand and gravel pits in the Deer Valley-Rescue-Shingle Springs area, just south of Lotus and a few miles east of Mt. Aukum. Serpentine material was also excavated by the county for “road metal” from the Hummingbird Ranch quarry one mile west of Garden Valley.
The El Dorado Dredging Corporation was a mining group that operated a one and one-half cubic yard dragline dredge on Greenwood, Coloma, Rock Canyon, and Irish Creeks during the years 1940-42 and again in 1948.
The El Dorado Limestone mine was an underground operation, three miles southwest of Shingle Springs. From it was produced high-calcium (97 percent plus) limestone for various uses including the manufacture of lime, steel and glass, beet-sugar refining and construction materials. Prior to the opening of the mine by the El Dorado Lime and Minerals company in 1918, limestone was quarried just north of the mine and burned in nearby stone lime kilns for building purposes. In 1931, the El Dorado Limestone Company was formed and operated the mine until it closed. The deposit consists of two lenses of limestone, one averaging sixty feet in width, the other forty feet. The main working entry is a 1000 foot, three compartment vertical shaft near the east wall of the east lens. Crosscuts extend from the shaft to the west lens. The deepest workings were at the 800 foot level. Because the material is solid, no timbering is required. In the 1970’s mining ceased and the shaft was allowed to flood with water. The crushing equipment on the surface continued to be used for several years, the limestone coming from the Gallo Glass mining operations at Marble Valley, to the west.
The El Dorado Slate Products Company (Chadborne) operated a slate mine on the south side of Big Canyon (apparently there are several Big Canyons in El Dorado County), one and one-half miles north of Placerville. Roofing slate was produced from several quarries during the 1920’s, which was then sent across the canyon via an overhead cable. Waste was sold for roofing granules.
The El Dorado Water and Deep Gravel Mining Company was another mining group that operated hydraulic and drift, placer gold mines on the ancient (tertiary) river beds in the Placerville area. Among their workings were the Coon Hollow (Big Cut) claim and the Excelsior Mine.
The Electric Consolidated mine was a lode gold mine on 14 acres of the Mother Lode, one-half mile north of Placerville.
The Elial L. Parker claim was on 120 acres of the Mother Lode, one mile south of Placerville.
The Elliott (Sir Walter Raleigh) mine was located on the Mother Lode, two miles south of Placerville. Around 1894 a four-foot vein of gold bearing quartz in slate was developed by a fifty-foot inclined shaft and crosscut adit.
The 19 acre Emma mine was located two miles northwest of Garden Valley on the western branch of the Mother Lode. Active before 1890, a four-foot vein of gold bearing quartz was worked by means of a 100-foot shaft.
The Empire placer mine was located on 20 acres one mile southeast of Georgetown, while the Empire lode claim was north of Volcanoville, just south of the Middle Fork of the American River.
The Encilan Mining Co. operated a placer mine one mile west of Omo Ranch on or near Brownsville Creek.
The Endress was a placer mine on 20 acres one mile northwest of Lotus near the South Fork of the American River.
The Enoch Redding mine was a placer mine two miles east of Fair Play in Slug Gulch.
The Enterprise Quartz mine was a lode mine on the Mother Lode on the northern side of Placerville, while the Enterprise Placer mine was on 49 acres in Randolph Canyon, north of Smith Flat.
The Epley and Mammoth (Epley Group) quartz claim consisted of 27 acres on the Mother Lode one mile south of Placerville.
The Equator Mine was three miles south of Diamond Springs, on the Mother Lode. Three veins of gold bearing quartz were developed by a 1300-foot crosscut adit and an 110-foot inclined shaft.
The Ernst Weber claim consisted of 120 acres one-half mile south of Placerville. From its location it appears to be a placer claim.
The Eskridge was a placer mine on the North Fork of the American River and is now under Folsom Lake.
The Esperanza mine was a lode gold mine located one mile northwest of Garden Valley on the western branch of the Mother Lode. Active in the last decade of the nineteenth century, it was developed by a 600-foot vertical shaft and 700 feet of drifts. The ore was treated in a 20-stamp mill. There was also another Esperanza mine one-half mile east of Greenwood that later became known as the Skipper Mine.
The Estelle was a lode mine consisting of 10 acres on the Mother Lode, two miles south of Kelsey.
The Ethel lode claim was six miles east of Garden Valley. Nothing else is known about it.
It is not surprising that there were at least six mines with the name of Eureka, it being the motto of the State of California. One of these became a part of the Woodside-Eureka mine, another a part of the immense workings of the Placerville Gold Mining Co. The Eureka mine just north of Georgetown was only active prior to 1888. Three parallel veins of gold bearing quartz, six to ten feet wide, were developed by a 240-foot inclined shaft and 500 feet of drifts. One Eureka lode mine was on 20 acres two miles west of the town of El Dorado while another was on 10 acres two miles west of Grizzly Flat.
Placer mines named Eureka were located on 37 acres one mile east of Kelsey, on 60 acres along the South Fork of the American River just north of Lotus and on a tributary of Weber Creek, one and one-half miles south of Placerville. This last one may have been the one controlled by the Placerville Gold Mining Co.
The Eureka Slate Quarry, operated by the Sierra Slate Company, was located one mile south of Kelsey. This was a big mining operation that was active for some forty years, from around 1886 until 1926. Dimension slate for a multitude of uses was mined from the quarry that had a 200-foot face and a depth of 200 feet. The mined slate was delivered to Placerville for transport on the railroad by means of a spectacular 13,000 foot long aerial tramway.
The Eusey was a placer mine consisted of 20 acres on the Cosumnes River in Nashville.
The Eusley was a placer mine on 50 acres two miles east of Fair Play in Slug Gulch.
The Ever mine was a chromite mine near Cothrin Station, between Shingle Springs and Latrobe. A 100 foot wide zone of small streaks and lenses of chromite was prospected in 1918. There are no production records available.
The Excelsior mine was adjacent to the Coon Hollow, one mile south of Placerville. Between the years 1852 and 1871, about five million dollars in gold was recovered by drifting and hydraulicking this ancient river channel, resulting in much of what is now known as Big Cut. Later, in the years 1907 – 11, the deposit was further worked by drifting. The gravel from the drifting operation was treated in a ten-stamp mill.
Three miles north of Shingle Springs was the Expansion, a lode gold mine. Here auriferous pyrite was the gold source. The deposit was worked form 1900-04 and later prospected in 1936. Mining was by way of a 150-foot crosscut adit.
The Extension of the Phillips and Joiner quartz mine consisted of nine acres two miles west of Grizzly Flat.