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Piestewa Peak area, Phoenix Mountains, Phoenix, Maricopa County, Arizona, USAi
Regional Level Types
Piestewa Peak areaArea
Phoenix MountainsMountain Range
PhoenixCity
Maricopa CountyCounty
ArizonaState
USACountry

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PhotosMapsSearch
01031000017272081032076.jpg
Viridine

Piestewa Peak area, Phoenix Mountains, Phoenix, Maricopa County, Arizona, USA
02270780017272081035955.jpg
Chloritoid

Piestewa Peak area, Phoenix Mountains, Phoenix, Maricopa County, Arizona, USA
01517620017272081046944.jpg
Kyanite

Piestewa Peak area, Phoenix Mountains, Phoenix, Maricopa County, Arizona, USA
07161660017271929099324.jpg
Viridine

Piestewa Peak area, Phoenix Mountains, Phoenix, Maricopa County, Arizona, USA
02270780017272081035955.jpg
Chloritoid

Piestewa Peak area, Phoenix Mountains, Phoenix, Maricopa County, Arizona, USA
01517620017272081046944.jpg
Kyanite

Piestewa Peak area, Phoenix Mountains, Phoenix, Maricopa County, Arizona, USA
03112020017271929194004.jpg
Viridine

Piestewa Peak area, Phoenix Mountains, Phoenix, Maricopa County, Arizona, USA
02270780017272081035955.jpg
Chloritoid

Piestewa Peak area, Phoenix Mountains, Phoenix, Maricopa County, Arizona, USA
Latitude & Longitude (WGS84):
33° 33' 43'' North , 112° 1' 14'' West
Latitude & Longitude (decimal):
33.56222,-112.02056
GRN:
N23W67
Type:
Area
Köppen climate type:
BSh : Hot semi-arid (steppe) climate
Mindat Locality ID:
54815
Long-form identifier:
mindat:1:2:54815:0
GUID (UUID V4):
0
Other/historical names associated with this locality:
Squaw Peak area


A group of kyanite occurrences on Piestewa Peak, especially the SW slope, and a nearby hill. A mining operation was conducted at some point and a recorded 38 tons of kyanite were mined. The mountain is within the Phoenix Mountain Preserve, and mineral and rock collecting are not allowed.

In 2003, the peak, formerly named Squaw Peak, was renamed Piestewa Peak, after Lori Ann Piestewa, the first Native American woman to die in combat while serving in the U.S. military.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


9 valid minerals.

Detailed Mineral List:

ⓘ Andalusite
Formula: Al2(SiO4)O
Description: Occurs in quartz-muscovite schist.
ⓘ Andalusite var. Viridine
Formula: (Al,Mn3+)2SiO4O
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Description: Occurs in a nearby hill.
ⓘ 'Chlorite Group'
Description: As manganese-rich porphyroblasts to 5 mm in schist.
ⓘ Chloritoid
Formula: Fe2+Al2O(SiO4)(OH)2
ⓘ 'Garnet Group'
Formula: X3Z2(SiO4)3
Description: Occurs in a nearby hill.
ⓘ Ilmenite
Formula: Fe2+TiO3
ⓘ Kanonaite
Formula: Mn3+Al(SiO4)O
Colour: Bright to dark green
Description: Occurs as blocky porphyroblasts to 1 cm diameter in quartz-muscovite schist.
ⓘ Kyanite
Formula: Al2(SiO4)O
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Piemontite
Formula: (CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
Habit: Acicular to bladed crystals to 3 mm long
Description: Occurs in quartz-muscovite schist.
ⓘ Spessartine
Formula: Mn2+3Al2(SiO4)3
Habit: Micro-crystals
Description: Occurs in schist.
ⓘ Staurolite
Formula: Fe2+2Al9Si4O23(OH)
Description: Occurs in a near by hill.
ⓘ Staurolite var. Zinc-bearing Staurolite
Formula: (Fe2+,Zn)2Al9Si4O23(OH)

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘIlmenite4.CB.05Fe2+TiO3
Group 9 - Silicates
ⓘSpessartine9.AD.25Mn2+3Al2(SiO4)3
ⓘAndalusite9.AF.10Al2(SiO4)O
ⓘKanonaite9.AF.10Mn3+Al(SiO4)O
ⓘAndalusite
var. Viridine		9.AF.10(Al,Mn3+)2SiO4O
ⓘKyanite9.AF.15Al2(SiO4)O
ⓘStaurolite9.AF.30Fe2+2Al9Si4O23(OH)
ⓘvar. Zinc-bearing Staurolite9.AF.30(Fe2+,Zn)2Al9Si4O23(OH)
ⓘChloritoid9.AF.85Fe2+Al2O(SiO4)(OH)2
ⓘPiemontite9.BG.05a(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
Unclassified
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Chlorite Group'-
ⓘ'Garnet Group'-X3Z2(SiO4)3

List of minerals for each chemical element

HHydrogen
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ ChloritoidFe2+Al2O(SiO4)(OH)2
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
Hⓘ StauroliteFe22+Al9Si4O23(OH)
Hⓘ Staurolite var. Zinc-bearing Staurolite(Fe2+,Zn)2Al9Si4O23(OH)
OOxygen
Oⓘ AndalusiteAl2(SiO4)O
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ ChloritoidFe2+Al2O(SiO4)(OH)2
Oⓘ IlmeniteFe2+TiO3
Oⓘ KanonaiteMn3+Al(SiO4)O
Oⓘ KyaniteAl2(SiO4)O
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
Oⓘ SpessartineMn32+Al2(SiO4)3
Oⓘ StauroliteFe22+Al9Si4O23(OH)
Oⓘ Andalusite var. Viridine(Al,Mn3+)2SiO4O
Oⓘ Garnet GroupX3Z2(SiO4)3
Oⓘ Staurolite var. Zinc-bearing Staurolite(Fe2+,Zn)2Al9Si4O23(OH)
FFluorine
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
MgMagnesium
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
AlAluminium
Alⓘ AndalusiteAl2(SiO4)O
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ ChloritoidFe2+Al2O(SiO4)(OH)2
Alⓘ KanonaiteMn3+Al(SiO4)O
Alⓘ KyaniteAl2(SiO4)O
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
Alⓘ SpessartineMn32+Al2(SiO4)3
Alⓘ StauroliteFe22+Al9Si4O23(OH)
Alⓘ Andalusite var. Viridine(Al,Mn3+)2SiO4O
Alⓘ Staurolite var. Zinc-bearing Staurolite(Fe2+,Zn)2Al9Si4O23(OH)
SiSilicon
Siⓘ AndalusiteAl2(SiO4)O
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ ChloritoidFe2+Al2O(SiO4)(OH)2
Siⓘ KanonaiteMn3+Al(SiO4)O
Siⓘ KyaniteAl2(SiO4)O
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
Siⓘ SpessartineMn32+Al2(SiO4)3
Siⓘ StauroliteFe22+Al9Si4O23(OH)
Siⓘ Andalusite var. Viridine(Al,Mn3+)2SiO4O
Siⓘ Garnet GroupX3Z2(SiO4)3
Siⓘ Staurolite var. Zinc-bearing Staurolite(Fe2+,Zn)2Al9Si4O23(OH)
KPotassium
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Tiⓘ IlmeniteFe2+TiO3
MnManganese
Mnⓘ KanonaiteMn3+Al(SiO4)O
Mnⓘ Piemontite(CaCa)(AlAlMn3+)O[Si2O7][SiO4](OH)
Mnⓘ SpessartineMn32+Al2(SiO4)3
Mnⓘ Andalusite var. Viridine(Al,Mn3+)2SiO4O
FeIron
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ ChloritoidFe2+Al2O(SiO4)(OH)2
Feⓘ IlmeniteFe2+TiO3
Feⓘ StauroliteFe22+Al9Si4O23(OH)
Feⓘ Staurolite var. Zinc-bearing Staurolite(Fe2+,Zn)2Al9Si4O23(OH)
ZnZinc
Znⓘ Staurolite var. Zinc-bearing Staurolite(Fe2+,Zn)2Al9Si4O23(OH)

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America 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

MRDS file #10060213.
Wilson, E.D. & G.H. Roseveare (1949), Arizona nonmetallics: A summary of past production and present operations (2nd. edition), Arizona Bureau of Mines Bulletin 155.
Elevatorski, E.A. (1978), Arizona Industrial Minerals, AZ Dept. of Min. Resources, Min Rpt. No. 2
Thorpe, D.G. & D.M. Burt (1980), A unique chloritoid-staurolite schist from near Squaw Peak, AZ, AZ Geol. Soc. Digest: 12: 193-200.
Peirce, H.W. (1990), AZ Geol. Sur. Industrial Minerals card file.
Anthony, John W., Williams, Sidney A., Bideaux, Richard A., Grant, Raymond W. (1995) Mineralogy of Arizona (3rd ed.). University of Arizona Press.pages 110, 171, 265, 271, 328, 376, 380
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