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Unnamed Mn occurrence [13], Cajon Pass, Cajon, San Bernardino County, California, USAi
Regional Level Types
Unnamed Mn occurrence [13]Occurrence
Cajon PassPass
Cajon- not defined -
San Bernardino CountyCounty
CaliforniaState
USACountry

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Latitude & Longitude (WGS84):
34° North , 117° West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~1km
GRN:
N23W70
Type:
Occurrence
Köppen climate type:
Csa : Hot-summer Mediterranean climate
Mindat Locality ID:
212263
Long-form identifier:
mindat:1:2:212263:5
GUID (UUID V4):
0


A Mn occurrence located W of the highway and immediately N of the pass's summit.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


2 valid minerals.

Detailed Mineral List:

ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
Description: Occurs in boulders and pebbles of quartz-mica schist with piemontite.
ⓘ Muscovite var. Alurgite
Formula: K(Al,Mn3+)2(AlSi3O10)(OH)2
Description: Occurs in boulders and pebbles of quartz-mica schist with piemontite.
ⓘ Piemontite
Formula: (CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
Description: Occurs in boulders and pebbles of quartz-mica schist and as piemontite schist pebbles in alluvial fans immediately N of the pass summit.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 9 - Silicates
ⓘPiemontite9.BG.05a(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
ⓘMuscovite
var. Alurgite		9.EC.15K(Al,Mn3+)2(AlSi3O10)(OH)2
ⓘ9.EC.15KAl2(AlSi3O10)(OH)2

List of minerals for each chemical element

HHydrogen
Hⓘ Muscovite var. AlurgiteK(Al,Mn3+)2(AlSi3O10)(OH)2
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
OOxygen
Oⓘ Muscovite var. AlurgiteK(Al,Mn3+)2(AlSi3O10)(OH)2
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
AlAluminium
Alⓘ Muscovite var. AlurgiteK(Al,Mn3+)2(AlSi3O10)(OH)2
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
SiSilicon
Siⓘ Muscovite var. AlurgiteK(Al,Mn3+)2(AlSi3O10)(OH)2
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
KPotassium
Kⓘ Muscovite var. AlurgiteK(Al,Mn3+)2(AlSi3O10)(OH)2
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
MnManganese
Mnⓘ Muscovite var. AlurgiteK(Al,Mn3+)2(AlSi3O10)(OH)2
Mnⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America Plate
Pacific 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

Webb, Robert W. (1939) Investigation of a new occurrence of alurgite from California. American Mineralogist, 24 (2) 123-129
Heinrich, E. Wm., Levinson, Alfred A. (1953) Studies in the mica group: Mineralogy of the rose muscovites. American Mineralogist, 38 (1-2) 25-49 p.41
Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 275, 289.
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