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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Sentinel Peak area, Tucson, Amole Mining District, Tucson Mountains, Pima County, Arizona, USAi
Regional Level Types
Sentinel Peak areaOccurrence
TucsonCity
Amole Mining DistrictMining District
Tucson MountainsMountain Range
Pima CountyCounty
ArizonaState
USACountry

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Latitude & Longitude (WGS84):
32° 12' 36'' North , 110° 59' 32'' West
Latitude & Longitude (decimal):
32.21025,-110.99234
GRN:
N22W67
Type:
Occurrence
Köppen climate type:
BSh : Hot semi-arid (steppe) climate
Nearest Settlements:
PlacePopulationDistance
South Tucson5,715 (2017)2.5km
Tucson531,641 (2017)6.3km
Drexel Heights27,749 (2011)8.4km
Flowing Wells16,419 (2011)9.4km
Tucson Estates12,192 (2011)9.6km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Old Pueblo Lapidary ClubTucson, Arizona6km
Tucson Gem and Mineral SocietyTucson, Arizona6km
Mindat Locality ID:
43083
Long-form identifier:
mindat:1:2:43083:3
GUID (UUID V4):
0
Other/historical names associated with this locality:
'A' Mountain area


An occurrence located near the 'A' Mountain.

'A' Mountain is a prominent feature of Tucson. The near side of the peak has a gigantic 'A' installed on it for the University of Arizona, located in Tucson, thus the name.

Mineralization is in geodes in basalt flows.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List

Mineral list contains entries from the region specified including sub-localities

2 valid minerals.

Detailed Mineral List:

ⓘ Anorthite
Formula: Ca(Al2Si2O8)
Description: Actually andesine-labradorite segment of the series. As phenocrysts to 2 inches (5 cm) in intrusive & flow porphyritic rocks, locally termed 'turkey-track porphyry.'
ⓘ Anorthite var. Labradorite
Formula: (Ca,Na)[Al(Al,Si)Si2O8]
Description: Actually andesine-labradorite segment of the series. As phenocrysts to 2 inches (5 cm) in intrusive & flow porphyritic rocks, locally termed 'turkey-track porphyry.'
ⓘ Quartz
Formula: SiO2
Description: As geodes in basalt flows.
ⓘ Quartz var. Agate
Formula: SiO2
Colour: Blue & white
Description: Occurs in abundant geodes in basalt flows.
ⓘ Quartz var. Chalcedony
Formula: SiO2
Colour: Blue & white
Description: Occurs in abundant geodes in basalt flows.
ⓘ Quartz var. Rock Crystal
Formula: SiO2
Description: Occurs in geodes in basalt flows.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘQuartz
var. Agate		4.DA.05SiO2
ⓘvar. Chalcedony4.DA.05SiO2
ⓘ4.DA.05SiO2
ⓘvar. Rock Crystal4.DA.05SiO2
Group 9 - Silicates
ⓘAnorthite9.FA.35Ca(Al2Si2O8)
ⓘvar. Labradorite9.FA.35(Ca,Na)[Al(Al,Si)Si2O8]

List of minerals for each chemical element

OOxygen
Oⓘ Quartz var. AgateSiO2
Oⓘ AnorthiteCa(Al2Si2O8)
Oⓘ Quartz var. ChalcedonySiO2
Oⓘ Anorthite var. Labradorite(Ca,Na)[Al(Al,Si)Si2O8]
Oⓘ QuartzSiO2
Oⓘ Quartz var. Rock CrystalSiO2
NaSodium
Naⓘ Anorthite var. Labradorite(Ca,Na)[Al(Al,Si)Si2O8]
AlAluminium
Alⓘ AnorthiteCa(Al2Si2O8)
Alⓘ Anorthite var. Labradorite(Ca,Na)[Al(Al,Si)Si2O8]
SiSilicon
Siⓘ Quartz var. AgateSiO2
Siⓘ AnorthiteCa(Al2Si2O8)
Siⓘ Quartz var. ChalcedonySiO2
Siⓘ Anorthite var. Labradorite(Ca,Na)[Al(Al,Si)Si2O8]
Siⓘ QuartzSiO2
Siⓘ Quartz var. Rock CrystalSiO2
CaCalcium
Caⓘ AnorthiteCa(Al2Si2O8)
Caⓘ Anorthite var. Labradorite(Ca,Na)[Al(Al,Si)Si2O8]

Localities in this Region

USA

Other Regions, Features and Areas containing this locality

Mexico
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

Galbraith, F.W. & Brennan (1959), Minerals of Arizona: 84, 85.
Guild, F.N. (1905), The petrography of the Tucson Mountains, American Journal of Science: 20: 313.
Anthony, John W., Williams, Sidney A., Bideaux, Richard A., Grant, Raymond W. (1995) Mineralogy of Arizona (3rd ed.). University of Arizona Press.pages 347, 348
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