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Gila Mountains Mica deposit, Fortuna Mine area, Barry M. Goldwater Air Force Range, Fortuna Mining District (La Fortuna Mining District), Yuma County, Arizona, USAi
Regional Level Types
Gila Mountains Mica depositDeposit
Fortuna Mine areaArea
Barry M. Goldwater Air Force RangeMountain Range
Fortuna Mining District (La Fortuna Mining District)Mining District
Yuma CountyCounty
ArizonaState
USACountry

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Latitude & Longitude (WGS84):
32° 33' 20'' North , 114° 18' 55'' West
Latitude & Longitude (decimal):
32.55556,-114.31528
GeoHash:
G#: 9my9nww1u
GRN:
N22W69
Type:
Deposit
Köppen climate type:
BWh : Hot deserts climate
Nearest Settlements:
PlacePopulationDistance
Fortuna Foothills26,265 (2011)14.5km
Wellton2,936 (2017)20.5km
El Prado Estates504 (2017)25.6km
Buckshot153 (2017)25.9km
Rancho Mesa Verde625 (2017)32.1km
Mindat Locality ID:
40705
Long-form identifier:
mindat:1:2:40705:7
GUID (UUID V4):
0


A Mica-Kaolin-Gypsum locality in sec. 15, T10S, R20W, in the central portion of the Gila Mountains, 2¼ miles E of the Fortuna Mine, on a military reservation. Claims held by Mr. S.E. Montgomery (1933). Phillips reported the location as sec. 23, T10S, R20W.

Mineralization is within pegmatite dikes that cut schist. Decomposed pegmatite dikes follow a fault zone for 1½ miles WSW-ward from the divide 2¼ miles East of the Fortune Mine. Schist near this dike shows intense alteration to coarse-grained sericite and for a distance of up to 150 feet on each side, is marked by brown and yellow limonitic stain.

Thin books of muscovite plates up to 3 inches across. Mica in decomposed portion of vein easily concentrated by washing. The mica is ruled and plicated, probably could only be used for grinding. Flaky muscovite and coarse-grained sericite.

Workings include a few surface cuts and short tunnels in 1929.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


3 valid minerals.

Detailed Mineral List:

ⓘ 'Garnet Group'
Formula: X3Z2(SiO4)3
ⓘ Gypsum
Formula: CaSO4 · 2H2O
ⓘ Kaolinite
Formula: Al2(Si2O5)(OH)4
Description: In decomposed pegmatite dike.
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
Description: In a decomposed pegmatite dike.
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
Description: Coarse-grained, in altered schist nr pegmatite dike.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘGypsum7.CD.40CaSO4 · 2H2O
Group 9 - Silicates
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘKaolinite9.ED.05Al2(Si2O5)(OH)4
Unclassified
ⓘ'Garnet Group'-X3Z2(SiO4)3

List of minerals for each chemical element

HHydrogen
Hⓘ GypsumCaSO4 · 2H2O
Hⓘ KaoliniteAl2(Si2O5)(OH)4
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
OOxygen
Oⓘ GypsumCaSO4 · 2H2O
Oⓘ KaoliniteAl2(Si2O5)(OH)4
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Oⓘ Garnet GroupX3Z2(SiO4)3
AlAluminium
Alⓘ KaoliniteAl2(Si2O5)(OH)4
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Siⓘ KaoliniteAl2(Si2O5)(OH)4
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Siⓘ Garnet GroupX3Z2(SiO4)3
SSulfur
Sⓘ GypsumCaSO4 · 2H2O
KPotassium
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ GypsumCaSO4 · 2H2O

Other Databases

Link to USGS MRDS:10060247

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

MRDS database Dep. ID file #10060247, MRDS ID #TC10230.
(1933) Geology and Mineral Deposits of Southern Yuma County, Arizona. University of Arizona Bulletin 134. Arizona Bureau of Minespp.201-202
(1969) Mineral and Water Resources of Arizona. University of Arizona Bulletin 180. Arizona Bureau of Minesp.871
Phillips, Ken A. (1987) Arizona Industrial Minerals - Department of Mines & Minerals Report #4 (2nd ed.). Arizona Department of Mines and Mineral Resources. 197 pp.
Peirce, H. Wesley (1990), Arizona Geological Survey Industrial Minerals card file.
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