Cummings Mine (Cummings lease; Section 13; Lone Tree; Winship property), Eagle Mountain, Ladd-Buckeye Mining District, San Joaquin County, California, USAi
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Latitude & Longitude (WGS84):
37° 35' 3'' North , 121° 29' 2'' West
Latitude & Longitude (decimal):
Type:
Köppen climate type:
Nearest Settlements:
| Place | Population | Distance |
|---|---|---|
| Tracy | 87,075 (2017) | 18.0km |
| Mountain House | 9,675 (2011) | 22.7km |
| Westley | 603 (2011) | 25.4km |
| Grayson | 952 (2011) | 26.9km |
| Livermore | 88,126 (2017) | 27.3km |
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 |
|---|---|---|
| Livermore Valley Lithophiles | Livermore, California | 27km |
| Mother Lode Mineral Society | Modesto, California | 43km |
| Stockton Lapidary & Mineral Club | Stockton, California | 45km |
| Santa Clara Valley Gem & Mineral Society | San Jose, California | 45km |
Mindat Locality ID:
91721
Long-form identifier:
mindat:1:2:91721:7
GUID (UUID V4):
a611907e-9267-47db-86da-a3944bf6e4d0
A former Mn mine located in sec. 13, T4S, R4E, MDM (UTM approximate), 5.0 km (3.1 miles) ENE of Eagle Mountain and 2.7 km (8,900 feet) SSE of the Ladd Mine, along the North Fork Lone Tree Creek, S of North Ridge. First produced in 1914. Owned by R. E. Naftzger, Beverley Hills, California (100.00%) (1976). Mineral rights are fee ownership. MRDS database stated accuracy for this location is 100 meters.
NOTE: MRDS database file #10207833 apparently applies to this locality; however, it presents data which are discrepant compared to the other 2 MRDS files. It presents a T&R value of sec. 34, T3S, R4E, MDM, and coordinates of 37.630710N, 121.526830W, and a MAS file #0060770067. It also states that local rocks include Plio-Pleistocene and Pliocene loosely consolidated deposits. The Pierce, et al reference is also derived from this MRDS file.
Mineralization is hosted in rocks of the Late Cretaceous Franciscan Complex, Calaveras Group - L (chert). The ore body strikes N45W and dips 60N at a thickness of 2 meters and a depth-to-top of 1 meter, a width of 25 meters and a length of 250 meters. The ore bodies are 1.) sedimentary and irregular, 2.) shear zone and 3.) disseminated. Primary mode of origin is sedimentary and the secondary mode was hydrothermal deposition. Primary ore control was bedding and the secondary mode was faulting. There is no wallrock alteration.
ore is in 3 beds through a stratigraphic thickness of 75 feet. The beds are faulted and consist of bementite, carbonate ore, high-grade oxide and disseminated oxide ore. Local rocks include rocks of the Franciscan melange.
Workings include surface and underground openings.
Analytical data results: Ore grade is 20 to 25% Mn.
Select Mineral List Type
Standard Detailed Gallery Strunz Chemical ElementsDetailed Mineral List:
| ⓘ Bementite Formula: Mn7Si6O15(OH)8 Description: Occurs as granulated masses as a constituent of ore. References: |
| ⓘ Inesite ? Formula: Ca2(Mn,Fe)7Si10O28(OH)2 · 5H2O Colour: Rose-red |
| ⓘ 'Psilomelane' |
| ⓘ Pyrolusite Formula: Mn4+O2 |
| ⓘ Rhodochrosite Formula: MnCO3 Colour: Gray Description: Occurs mixed with bementite. References: |
Gallery:
List of minerals arranged by Strunz 10th Edition classification
| Group 4 - Oxides and Hydroxides | |||
|---|---|---|---|
| ⓘ | Pyrolusite | 4.DB.05 | Mn4+O2 |
| Group 5 - Nitrates and Carbonates | |||
| ⓘ | Rhodochrosite | 5.AB.05 | MnCO3 |
| Group 9 - Silicates | |||
| ⓘ | Inesite ? | 9.DL.05 | Ca2(Mn,Fe)7Si10O28(OH)2 · 5H2O |
| ⓘ | Bementite | 9.EE.05 | Mn7Si6O15(OH)8 |
| Unclassified | |||
| ⓘ | 'Psilomelane' | - | |
List of minerals for each chemical element
| H | Hydrogen | |
|---|---|---|
| H | ⓘ Bementite | Mn7Si6O15(OH)8 |
| H | ⓘ Inesite | Ca2(Mn,Fe)7Si10O28(OH)2 · 5H2O |
| C | Carbon | |
| C | ⓘ Rhodochrosite | MnCO3 |
| O | Oxygen | |
| O | ⓘ Bementite | Mn7Si6O15(OH)8 |
| O | ⓘ Inesite | Ca2(Mn,Fe)7Si10O28(OH)2 · 5H2O |
| O | ⓘ Pyrolusite | Mn4+O2 |
| O | ⓘ Rhodochrosite | MnCO3 |
| Si | Silicon | |
| Si | ⓘ Bementite | Mn7Si6O15(OH)8 |
| Si | ⓘ Inesite | Ca2(Mn,Fe)7Si10O28(OH)2 · 5H2O |
| Ca | Calcium | |
| Ca | ⓘ Inesite | Ca2(Mn,Fe)7Si10O28(OH)2 · 5H2O |
| Mn | Manganese | |
| Mn | ⓘ Bementite | Mn7Si6O15(OH)8 |
| Mn | ⓘ Inesite | Ca2(Mn,Fe)7Si10O28(OH)2 · 5H2O |
| Mn | ⓘ Pyrolusite | Mn4+O2 |
| Mn | ⓘ Rhodochrosite | MnCO3 |
| Fe | Iron | |
| Fe | ⓘ Inesite | Ca2(Mn,Fe)7Si10O28(OH)2 · 5H2O |
Other Databases
| Link to USGS MRDS: | 10033550 |
|---|
Other Regions, Features and Areas containing this locality
North America
- Coast MountainsMountain Range
North America PlateTectonic Plate
- Franciscan DomainDomain
- Great Valley BasinBasin
USA
- California
- Diablo RangeMountain Range
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References
(n.d.) Minerals Availability System (MAS), U.S. Bureau of Mines.file ID #0060770002
