Cosumnes Mine (Cosumnes Melton; Melton; Middle End), Grizzly Flat, Grizzly Flat Mining District, East Belt, El Dorado County, California, USAi
| Regional Level Types | |
|---|---|
| Cosumnes Mine (Cosumnes Melton; Melton; Middle End) | Mine |
| Grizzly Flat | - not defined - |
| Grizzly Flat Mining District | Mining District |
| East Belt | - not defined - |
| El Dorado County | County |
| California | State |
| USA | Country |
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Latitude & Longitude (WGS84):
38° 39' 53'' North , 120° 32' 0'' West
Latitude & Longitude (decimal):
Type:
Köppen climate type:
Nearest Settlements:
| Place | Population | Distance |
|---|---|---|
| Pollock Pines | 6,871 (2017) | 11.7km |
| Camino | 1,750 (2011) | 14.8km |
| River Pines | 379 (2011) | 22.5km |
| Buckhorn | 2,429 (2017) | 23.6km |
| Placerville | 10,650 (2017) | 24.1km |
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
Local clubs are the best way to get access to collecting localities
| Club | Location | Distance |
|---|---|---|
| El Dorado County Mineral and Gem Society | Placerville, California | 24km |
| Gold Country Treasure Seekers | Placerville, California | 24km |
| Amador County Gem & Mineral Society | Sutter Creek, California | 38km |
A former lode Cu-Au-Zn-Pb-Ag-Sb occurrence/mine located in secs. 3 & 4, T9N, R13E, MDM, 3.2 km (2.0 miles) N of Grizzly Flat, just S of the Cosumnes River, on private land. Operated by the Caldor Lumber Company. Operated in the 1880's, 1894, 1928 to 1942 & 1942 to 1951. MRDS database stated accuracy for this location is 100 meters. Active during the 1880's and in 1894 as the Melton Mine; reopened in 1928 as the Middle End Mine and operated almost continuously until 1942. Operated by the Cosumnes Mines, Inc. from 1945 to 1950, when purchased by the present owner. The workings are shown in the W½NW¼ sec. 3 on USGS topo map.
Mineralization is a vein deposit hosted in diorite. The ore body strikes NNE and dips W at a thickness of 0.91 meter. Most ore was from the Main or Middle vein that dips steeply at an average of 3 feet thick. Appreciable amounts of galena and pyrite, with sphalerite, chalcopyrite, stibnite and arsenopyrite are present in the ore. Local rocks include Mesozoic gabbroic rocks, unit 2 (undivided).
Workings include underground openings comprised of a 380 foot crosscut adit and several thousand feet of drifts.
Production data are found in: Goodwin, Joseph Grant (1957).
About 10,000 pounds of Pb and some Cu were produced during the period 1928 to 1951, in addition to Au & Ag.
During the last years of production the ore contained up to $25 (period values) Au/ton with sulfide concentrates yielding $100 to $200 (period values) Au/ton.
Mineralization is a vein deposit hosted in diorite. The ore body strikes NNE and dips W at a thickness of 0.91 meter. Most ore was from the Main or Middle vein that dips steeply at an average of 3 feet thick. Appreciable amounts of galena and pyrite, with sphalerite, chalcopyrite, stibnite and arsenopyrite are present in the ore. Local rocks include Mesozoic gabbroic rocks, unit 2 (undivided).
Workings include underground openings comprised of a 380 foot crosscut adit and several thousand feet of drifts.
Production data are found in: Goodwin, Joseph Grant (1957).
About 10,000 pounds of Pb and some Cu were produced during the period 1928 to 1951, in addition to Au & Ag.
During the last years of production the ore contained up to $25 (period values) Au/ton with sulfide concentrates yielding $100 to $200 (period values) Au/ton.
Select Mineral List Type
Standard Detailed Gallery Strunz Chemical ElementsDetailed Mineral List:
| ⓘ Arsenopyrite Formula: FeAsS |
| ⓘ Chalcopyrite Formula: CuFeS2 |
| ⓘ Galena Formula: PbS |
| ⓘ Native Gold Formula: Au |
| ⓘ Pyrite Formula: FeS2 |
| ⓘ Quartz Formula: SiO2 |
| ⓘ Sphalerite Formula: ZnS |
| ⓘ Stibnite Formula: Sb2S3 References: |
Gallery:
List of minerals arranged by Strunz 10th Edition classification
| Group 1 - Elements | |||
|---|---|---|---|
| ⓘ | Native Gold | 1.AA.05 | Au |
| Group 2 - Sulphides and Sulfosalts | |||
| ⓘ | Sphalerite | 2.CB.05a | ZnS |
| ⓘ | Chalcopyrite | 2.CB.10a | CuFeS2 |
| ⓘ | Galena | 2.CD.10 | PbS |
| ⓘ | Stibnite | 2.DB.05 | Sb2S3 |
| ⓘ | Pyrite | 2.EB.05a | FeS2 |
| ⓘ | Arsenopyrite | 2.EB.20 | FeAsS |
| Group 4 - Oxides and Hydroxides | |||
| ⓘ | Quartz | 4.DA.05 | SiO2 |
List of minerals for each chemical element
| O | Oxygen | |
|---|---|---|
| O | ⓘ Quartz | SiO2 |
| Si | Silicon | |
| Si | ⓘ Quartz | SiO2 |
| S | Sulfur | |
| S | ⓘ Arsenopyrite | FeAsS |
| S | ⓘ Chalcopyrite | CuFeS2 |
| S | ⓘ Galena | PbS |
| S | ⓘ Pyrite | FeS2 |
| S | ⓘ Sphalerite | ZnS |
| S | ⓘ Stibnite | Sb2S3 |
| Fe | Iron | |
| Fe | ⓘ Arsenopyrite | FeAsS |
| Fe | ⓘ Chalcopyrite | CuFeS2 |
| Fe | ⓘ Pyrite | FeS2 |
| Cu | Copper | |
| Cu | ⓘ Chalcopyrite | CuFeS2 |
| Zn | Zinc | |
| Zn | ⓘ Sphalerite | ZnS |
| As | Arsenic | |
| As | ⓘ Arsenopyrite | FeAsS |
| Sb | Antimony | |
| Sb | ⓘ Stibnite | Sb2S3 |
| Au | Gold | |
| Au | ⓘ Native Gold | Au |
| Pb | Lead | |
| Pb | ⓘ Galena | PbS |
Other Databases
| Link to USGS MRDS: | 10030434 |
|---|
Other Regions, Features and Areas containing this locality
North AmericaContinent
North America PlateTectonic Plate
- Shoofly-Olds Ferry DomainDomain
- Sierra Nevada BatholithVolcanic Arc
USA
- Sierra NevadaMountain Range
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References
(n.d.) Minerals Availability System (MAS), U.S. Bureau of Mines.file #0060171082
