Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite
Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
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Friday Mine, Julian, Julian Mining District, San Diego County, California, USAi
Regional Level Types
Friday MineMine
Julian- not defined -
Julian Mining DistrictMining District
San Diego CountyCounty
CaliforniaState
USACountry

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Latitude & Longitude (WGS84):
33° 4' North , 116° 36' West
Latitude & Longitude (decimal):
33.06667,-116.60000
GeoHash:
G#: 9mvh4ew7r
GRN:
N23W70
Type:
Mine
Köppen climate type:
Csa : Hot-summer Mediterranean climate
Nearest Settlements:
PlacePopulationDistance
Julian1,502 (2011)1.3km
San Diego Country Estates10,109 (2011)18.4km
Descanso1,423 (2011)23.8km
Ramona20,292 (2011)25.1km
Pine Valley1,510 (2011)28.0km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Borrego Rock and Gem ClubBorrego Springs, California30km
El Cajon Valley Gem & Mineral SocietyEl Cajon, California45km
Palomar Gem & Mineral ClubEscondido, California46km
Mindat Locality ID:
11243
Long-form identifier:
mindat:1:2:11243:2
GUID (UUID V4):
0


A former Cu-Ni-Co mine located in the SW¼ sec. 15, T13S, R4E, SBM, 4 miles S of Julian.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


11 valid minerals.

Detailed Mineral List:

ⓘ Chalcopyrite
Formula: CuFeS2
Description: Occurs in massive pyrrhotite.
ⓘ Erythrite
Formula: Co3(AsO4)2 · 8H2O
Description: Occurs in the oxidized zone.
ⓘ Hydromagnesite
Formula: Mg5(CO3)4(OH)2 · 4H2O
Description: Occurs as minute hollow spherules in pyrrhotite ore.
ⓘ 'Limonite'
Description: Occurs in the oxidized zone.
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Morenosite
Formula: NiSO4 · 7H2O
Description: Occurs in the oxidized zone.
ⓘ Pentlandite
Formula: (NixFey)Σ9S8
Description: Occurs as residual cores in violarite in massive pyrrhotite.
ⓘ Pyrite
Formula: FeS2
Description: Occurs as compact botryoidal material in veins cutting pyrrhotite. Crystallized FeS2 gel which exhibits a banded, gel-like structure; very hard.
ⓘ Pyrrhotite
Formula: Fe1-xS
ⓘ Pyrrhotite var. Nickel-bearing Pyrrhotite
Formula: (Fe,Ni)7S8
Description: Occurs on the contact of gabbro and fine-grained schist.
ⓘ Quartz
Formula: SiO2
ⓘ Siderite
Formula: FeCO3
ⓘ Violarite
Formula: Fe2+Ni3+2S4

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘPentlandite2.BB.15(NixFey)Σ9S8
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘPyrrhotite2.CC.10Fe1-xS
ⓘvar. Nickel-bearing Pyrrhotite2.CC.10(Fe,Ni)7S8
ⓘViolarite2.DA.05Fe2+Ni3+2S4
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘQuartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘSiderite5.AB.05FeCO3
ⓘHydromagnesite5.DA.05Mg5(CO3)4(OH)2 · 4H2O
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘMorenosite7.CB.40NiSO4 · 7H2O
Group 8 - Phosphates, Arsenates and Vanadates
ⓘErythrite8.CE.40Co3(AsO4)2 · 8H2O
Unclassified
ⓘ'Limonite'-

List of minerals for each chemical element

HHydrogen
Hⓘ ErythriteCo3(AsO4)2 · 8H2O
Hⓘ HydromagnesiteMg5(CO3)4(OH)2 · 4H2O
Hⓘ MorenositeNiSO4 · 7H2O
CCarbon
Cⓘ HydromagnesiteMg5(CO3)4(OH)2 · 4H2O
Cⓘ SideriteFeCO3
OOxygen
Oⓘ ErythriteCo3(AsO4)2 · 8H2O
Oⓘ HydromagnesiteMg5(CO3)4(OH)2 · 4H2O
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ MorenositeNiSO4 · 7H2O
Oⓘ QuartzSiO2
Oⓘ SideriteFeCO3
MgMagnesium
Mgⓘ HydromagnesiteMg5(CO3)4(OH)2 · 4H2O
SiSilicon
Siⓘ QuartzSiO2
SSulfur
Sⓘ ChalcopyriteCuFeS2
Sⓘ MorenositeNiSO4 · 7H2O
Sⓘ Pentlandite(NixFey)Σ9S8
Sⓘ PyriteFeS2
Sⓘ PyrrhotiteFe1-xS
Sⓘ ViolariteFe2+Ni23+S4
Sⓘ Pyrrhotite var. Nickel-bearing Pyrrhotite(Fe,Ni)7S8
FeIron
Feⓘ ChalcopyriteCuFeS2
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ Pentlandite(NixFey)Σ9S8
Feⓘ PyriteFeS2
Feⓘ PyrrhotiteFe1-xS
Feⓘ SideriteFeCO3
Feⓘ ViolariteFe2+Ni23+S4
Feⓘ Pyrrhotite var. Nickel-bearing Pyrrhotite(Fe,Ni)7S8
CoCobalt
Coⓘ ErythriteCo3(AsO4)2 · 8H2O
NiNickel
Niⓘ MorenositeNiSO4 · 7H2O
Niⓘ Pentlandite(NixFey)Σ9S8
Niⓘ ViolariteFe2+Ni23+S4
Niⓘ Pyrrhotite var. Nickel-bearing Pyrrhotite(Fe,Ni)7S8
CuCopper
Cuⓘ ChalcopyriteCuFeS2
AsArsenic
Asⓘ ErythriteCo3(AsO4)2 · 8H2O

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America Plate
Pacific PlateTectonic Plate

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

Calkins, F.C. (1916), An occurrence of nickel ore in San Diego County, California: USGS Bulletin 640: 78, 79
Hudson, Frank Samuel (1922), Geology of the Cuyamaca region of California with special reference to the origin of the Nickeliferous pyrrhotite: University of California, Department of Geological Sciences Bulletin: 13: 214, 217, 219.
Short, M. N., Shannon, Earl V. (1930) Violarite and other rare nickel sulphides. American Mineralogist, 15 (1) 1-22 p.8
Donnelly, Maurice (1934), Geology and mineral deposits of the Julian district, San Diego County, California: California Division Mines Report 30: 331-370; […(abstract): Geological Society of America Proc. 1934: 321 (1934)]: 370.
Palache, Charles, Berman, Harry, Frondel, Clifford (1944) The System of Mineralogy (7th ed.) Vol. 1 - Elements, Sulfides, Sulfosalts, Oxides. John Wiley and Sons, New York.
Creasey, S.C. (1946), Geology and nickel mineralization of the Julian-Cuyamaca area, San Diego County, California: California Division Mines Report 42: 27
Weber, F. Harold Jr. (1963) Geology and mineral resources of San Diego County, California. County Report 3. California Division of Mines and Geology p.196
Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 133, 179, 222, 274, 285, 302, 312, 381.
Pemberton, H. Earl (1983) Minerals of California. Van Nostrand Reinhold Company Inc.
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