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Caldwell Mine (Daly Mine), Granite Springs, Granite Springs Mining District, West Belt, Mariposa County, California, USAi
Regional Level Types
Caldwell Mine (Daly Mine)Mine
Granite SpringsGroup of Springs
Granite Springs Mining DistrictMining District
West Belt- not defined -
Mariposa CountyCounty
CaliforniaState
USACountry

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Latitude & Longitude (WGS84):
37° 40' 51'' North , 120° 16' 49'' West
Latitude & Longitude (decimal):
37.68083,-120.28028
GeoHash:
G#: 9qdqqgwdf
GRN:
N26W68
Type:
Mine
Köppen climate type:
Csa : Hot-summer Mediterranean climate
Nearest Settlements:
PlacePopulationDistance
Coulterville201 (2011)8.0km
Greeley Hill915 (2011)15.0km
Groveland601 (2011)18.0km
Bear Valley125 (2011)18.9km
Snelling231 (2011)22.7km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Mariposa Gem & Mineral ClubMariposa, California35km
Calaveras Gem & Mineral SocietyAngels Camp, California49km
Mindat Locality ID:
82052
Long-form identifier:
mindat:1:2:82052:2
GUID (UUID V4):
0


A former Mn mine located in the SE¼SE¼ sec. 11 & in the NE¼NE¼ sec. 14, T3S, R15E, MDM, 2.6 km (8,600 feet) SSE of Granite Springs (town), on private (patented) land. Discovered in 1917. Property consists of patented agricultual land. Owned by Robert D. Dunn (1974). Operated by Walter Hixson, California (1974). MRDS database stated accuracy for this location is 1,000 meters.

Mineralization is an Mn deposit hosted in chert. The ore body strikes N12E and dips 65E. The chert is enclosed in metatuff and metavolcanics. The Mn is associated with the chert as a series of lenses enclosed in the chert. The thick-bedded to massive red chert, thin-bedded buff to gray chert, and massive to thick-bedded white chert is enclosed in gray to green metatuff and metavolcanics of the Amador group. The ore is partly psilomelane, but is mainly brown, gray or rose-colored cherty manganiferous calcium carbonate (manganocalcite). Pyrolusite is also present. Local rocks include Mesozoic volcanic rocks, unit 2 (Western Sierra Foothills and Western Klamath Mountains).

Workings include surface and underground openings comprised of an inclined shaft 57 feet deep with a 26 foot drift at its bottom, a 10 foot deep shaft, a 15 foot shaft plus 30 open cuts scattered along the ore zone for a distance of more than 1,000 feet.

Operated during WWI as the Daly Mine, producing between 100-200 tons of ore which averaged 45% Mn, 6% Fe, and 13% silica. Reactivated about 1937 and operated until 1943. Total production has been about 265 tons of ore averaging nearly 45% Mn.

Ore running at least 20% Mn remained in the mine in 1942.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


7 valid minerals.

Detailed Mineral List:

ⓘ Bementite
Formula: Mn7Si6O15(OH)8
ⓘ Calcite
Formula: CaCO3
Description: 20% to 30% Mn.
ⓘ Calcite var. Manganese-bearing Calcite
Formula: (Ca,Mn)CO3
Description: 20% to 30% Mn.
ⓘ Hausmannite
Formula: Mn2+Mn3+2O4
ⓘ Piemontite
Formula: (CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
Description: Occurs as grains in ore.
ⓘ 'Psilomelane'
ⓘ Pyrolusite
Formula: Mn4+O2
ⓘ Rhodonite
Formula: CaMn3Mn[Si5O15]
ⓘ Tephroite
Formula: Mn2+2SiO4
Description: Occurs as micro-crystals of plumose material.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘHausmannite4.BB.10Mn2+Mn3+2O4
ⓘPyrolusite4.DB.05Mn4+O2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘvar. Manganese-bearing Calcite5.AB.05(Ca,Mn)CO3
Group 9 - Silicates
ⓘTephroite9.AC.05Mn2+2SiO4
ⓘPiemontite9.BG.05a(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
ⓘRhodonite9.DK.05CaMn3Mn[Si5O15]
ⓘBementite9.EE.05Mn7Si6O15(OH)8
Unclassified
ⓘ'Psilomelane'-

List of minerals for each chemical element

HHydrogen
Hⓘ BementiteMn7Si6O15(OH)8
Hⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
CCarbon
Cⓘ CalciteCaCO3
Cⓘ Calcite var. Manganese-bearing Calcite(Ca,Mn)CO3
OOxygen
Oⓘ BementiteMn7Si6O15(OH)8
Oⓘ CalciteCaCO3
Oⓘ HausmanniteMn2+Mn23+O4
Oⓘ Calcite var. Manganese-bearing Calcite(Ca,Mn)CO3
Oⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
Oⓘ PyrolusiteMn4+O2
Oⓘ RhodoniteCaMn3Mn[Si5O15]
Oⓘ TephroiteMn22+SiO4
AlAluminium
Alⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
SiSilicon
Siⓘ BementiteMn7Si6O15(OH)8
Siⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
Siⓘ RhodoniteCaMn3Mn[Si5O15]
Siⓘ TephroiteMn22+SiO4
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ Calcite var. Manganese-bearing Calcite(Ca,Mn)CO3
Caⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
Caⓘ RhodoniteCaMn3Mn[Si5O15]
MnManganese
Mnⓘ BementiteMn7Si6O15(OH)8
Mnⓘ HausmanniteMn2+Mn23+O4
Mnⓘ Calcite var. Manganese-bearing Calcite(Ca,Mn)CO3
Mnⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
Mnⓘ PyrolusiteMn4+O2
Mnⓘ RhodoniteCaMn3Mn[Si5O15]
Mnⓘ TephroiteMn22+SiO4

Other Databases

Link to USGS MRDS:10188131

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate
USA

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

DMEA application - 2952 - reported 7/13/53 by Wiekelt - no contract, DMEA index: 16.
(n.d.) Minerals Availability System (MAS), U.S. Bureau of Mines.file ID #0060430001
U.S. Bureau of Mines Report of Investigation 5163: 7.
Taliaferro, Nicholas Lloyd & A.J. Solari (1943a), Manganese deposits of the Sierra Nevada: their genesis and metamorphism: California Division Mines and Geology Bulletin 125: 326
Trask, Parker Davies, Ivan F. Wilson & F.S. Simons (1943), Manganese deposits of California – a summary report: California Division Mines Bulletin 125: 80
Trask, Parker Davies (1950) Geologic description of the manganese deposits of California. California Division of Mines Bulletin 152, 378 pp.: 106-108
Bowen, O.E., Jr. & C.H. Gray, Jr. (1957), Mines and mineral deposits of Mariposa County, California: California Journal of Mines and Geology: 53(1&2): 191, 324, Pl. 4
Trengrove, Russell R. (1960), Reconnaissance of California Manganese Deposits, U.S. Bureau of Mines Report of Investigation 5579: 23-24.
Hewett, Donnel Foster, Chesterman, Charles Wesley, Troxel, Bennie Wyatt (1961) Tephroite in California manganese deposits. Economic Geology, 56 (1). 39-58 doi:10.2113/gsecongeo.56.1.39pp.50-52
Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 214, 361
Pemberton, H. Earl (1983) Minerals of California. Van Nostrand Reinhold Company Inc.
(2005) Mineral Resources Data System (MRDS), US Geological Survey.
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