| Deposit ID | 10139515 |
|---|---|
| MRDS ID | M007808 |
| MAS/MILS ID | 0060170022 |
| Record type | Site |
| Current site name | O'Brien Mine |
| Alternate or previous names | S-Bend Mine |
| Related records | 10029957 |
| Point of reference | Main Entrance |
|---|---|
| Geographic coordinates: | -120.89743, 38.826 (WGS84) |
| Elevation | 439 |
| Location accuracy | 10(meters) |
Political divisions (FIPS codes)
El Dorado(county)
California(state)
United States(country)
North America(continent)
Land(continent)
USGS map quadrangles
Coloma(quadrangle 1:24,000 scale)
Placerville(quadrangle 1:100,000 scale)
Sacramento(quadrangle 1:250,000 scale)
Hydrologic units (watersheds)
South Fork American(hydrologic unit)
Lower Sacramento(hydrologic accounting unit)
Sacramento(hydrologic subregion)
California(hydrologic region)
| Country | State | County |
|---|---|---|
| United States | California | El Dorado |
| Meridian | Township | Range | Section | Fraction | State |
|---|---|---|---|---|---|
| Mount Diablo | 011 N | 010 E | 07 | NWNENE | California |
| Commodity | Importance |
|---|---|
| Chromium Critical | Tertiary |
| Iron | Tertiary |
| Materials | Type of material |
|---|---|
| Chromite | Unknown |
| Olivine | Unknown |
| Pyroxene | Unknown |
| Serpentine | Unknown |
| Talc | Unknown |
| Main Entrance (1) | -120.89743, 38.826 |
|---|
| Strike | N35W | ||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dip | 53S | ||||||||||||||||||||||||||||||||||||
| Thickness | 1M | ||||||||||||||||||||||||||||||||||||
| Length | 20M | ||||||||||||||||||||||||||||||||||||
| Width | 10M | ||||||||||||||||||||||||||||||||||||
| Area | 1HA | ||||||||||||||||||||||||||||||||||||
| Depth to top | 0M | ||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||
| Operation type | Underground |
|---|---|
| Development status | Past Producer |
| Commodity type | Metallic |
| Significant | No |
| Discovery year | 1917 |
| Year of first production | 1918 |
| District name | Garden Valley Area |
|---|
| Type of mineral rights | Patented |
|---|---|
| Type of mineral rights | Private Lease |
| Ownership category | Private |
|---|
| Type | Owner |
|---|---|
| Owner | Maragret G Bell,1976 |
| Interest | 100 |
| Home office | California |
| Year | 1976 |
| Type | Operator |
|---|---|
| Owner | Volo Mining Co., Last Operator 1942 |
| Home office | California |
| Year | 1976 |
| Type | In-situ | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Estimate year | 1979 | |||||||||||||||||||||
| Indicated | 254mt ore | |||||||||||||||||||||
| Demonstrated | 254mt ore | |||||||||||||||||||||
| Inferred | 765mt ore | |||||||||||||||||||||
| Total resources | 765000mt ore | |||||||||||||||||||||
| ||||||||||||||||||||||
| Agency | Database name | Acronym | Record ID | Notes |
|---|---|---|---|---|
| U.S. Bureau of Mines | Minerals Availability System | MAS | 0060170022 | |
| USGS | Mineral Resources Data System | MRDS | M007808 | MAS references MRDS |
COOP WAR MINERALS INVESTIG. EL DORADO CO. NO.28 1918, TALIA
CATER, CALIF DIV MINES BULL, 134,PT 3,CH 4,P.156, 1951
| Subject category | Comment text |
|---|---|
| Deposit | AVERAGE GRADE OF ORE SHIPPED IN 1918 WAS 32-34% CR2O3, FROM TOTAL PRODUCTION APPROX 3200 TO 3500 TONS, RECORD 700 AND RESERVE ESTIMATES BASED ON CATERSOBSERVATION, CITED FROM REC INSUFFICIENT ORE FOR COSTING ANALYSIS BY CDMG IN 1976 GAVE FOLLOWING PERCENTAGES-DISSEMIN E=S102 03.69,CR2O3 43.85,FEO 10.65,TOTAL FE 12.87,AL203 19.8 9.07,CR/FE 3.00. |
| Type | Date | Name | Affiliation | Comment |
|---|---|---|---|---|
| Reporter | 27-FEB-1984 | Wetzel, Nicholas | U.S. Bureau of Mines |
Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.
These are landing pages for further research — the state agencies don't currently expose per-mine deep links.