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Sweetwater Mine, Cerro Alto, Santa Lucia Mts (Santa Lucia Range), San Luis Obispo County, California, USAi
Regional Level Types
Sweetwater MineMine
Cerro AltoMountain
Santa Lucia Mts (Santa Lucia Range)Mountain Range
San Luis Obispo CountyCounty
CaliforniaState
USACountry

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PhotosMapsSearch
03423320017272095569977.jpg
Aragonite

Sweetwater Mine, Cerro Alto, Santa Lucia Mts, San Luis Obispo County, California, USA
03423320017272095569977.jpg
Aragonite

Sweetwater Mine, Cerro Alto, Santa Lucia Mts, San Luis Obispo County, California, USA
03423320017272095569977.jpg
Aragonite

Sweetwater Mine, Cerro Alto, Santa Lucia Mts, San Luis Obispo County, California, USA
Latitude & Longitude (WGS84):
35° 25' 5'' North , 120° 45' 12'' West
Latitude & Longitude (decimal):
35.41806,-120.75361
GeoHash:
G#: 9q61kptvh
GRN:
N24W71
Type:
Mine
Köppen climate type:
Csb : Warm-summer Mediterranean climate
Nearest Settlements:
PlacePopulationDistance
Morro Bay10,639 (2017)10.5km
Atascadero29,819 (2017)10.9km
Cayucos2,592 (2011)12.8km
Garden Farms386 (2011)13.3km
Santa Margarita1,259 (2014)13.5km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Central Coast Treasure Hunters AssociationSan Luis Obispo, California17km
San Luis Obispo Gem & Mineral ClubSan Luis Obispo, California17km
Santa Lucia RockhoundsPaso Robles, California24km
Mindat Locality ID:
91994
Long-form identifier:
mindat:1:2:91994:1
GUID (UUID V4):
0
Other/historical names associated with this locality:
San Juan Mine; Pierce and Benadom group


A former Cr-PGE (Pt-Pd-Rh-Ru-Ir) mine located 1.8 km (5,900 feet) WNW of Cerro Alto and about 6 miles NE of Morro Bay in the Coast Ranges.

Mineralization is a Cr deposit (Deposit model: 15: Podiform chromite (minor)), hosted in dunite.

Local structures include prevalent shearing.

Related tectonic structures include the California Coast Ranges.

Production data are found in: Stinson (1975).

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


4 valid minerals. 1 erroneous literature entry.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘChromite ?4.BB.05Fe2+Cr3+2O4
ⓘHercynite4.BB.05Fe2+Al2O4
ⓘMagnesiochromite4.BB.05MgCr2O4
ⓘSpinel4.BB.05MgAl2O4
ⓘHercynite
var. Picotite		4.BB.05(Fe,Mg)(Al,Cr)2O4
Group 9 - Silicates
ⓘAntigorite9.ED.15Mg3(Si2O5)(OH)4

List of minerals for each chemical element

HHydrogen
Hⓘ AntigoriteMg3(Si2O5)(OH)4
OOxygen
Oⓘ AntigoriteMg3(Si2O5)(OH)4
Oⓘ ChromiteFe2+Cr23+O4
Oⓘ HercyniteFe2+Al2O4
Oⓘ MagnesiochromiteMgCr2O4
Oⓘ SpinelMgAl2O4
Oⓘ Hercynite var. Picotite(Fe,Mg)(Al,Cr)2O4
MgMagnesium
Mgⓘ AntigoriteMg3(Si2O5)(OH)4
Mgⓘ MagnesiochromiteMgCr2O4
Mgⓘ SpinelMgAl2O4
Mgⓘ Hercynite var. Picotite(Fe,Mg)(Al,Cr)2O4
AlAluminium
Alⓘ HercyniteFe2+Al2O4
Alⓘ SpinelMgAl2O4
Alⓘ Hercynite var. Picotite(Fe,Mg)(Al,Cr)2O4
SiSilicon
Siⓘ AntigoriteMg3(Si2O5)(OH)4
CrChromium
Crⓘ ChromiteFe2+Cr23+O4
Crⓘ MagnesiochromiteMgCr2O4
Crⓘ Hercynite var. Picotite(Fe,Mg)(Al,Cr)2O4
FeIron
Feⓘ ChromiteFe2+Cr23+O4
Feⓘ HercyniteFe2+Al2O4
Feⓘ Hercynite var. Picotite(Fe,Mg)(Al,Cr)2O4

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

Bradley, W.W., Huguenin, Emile, Logan, C.A., Tucker, W.B., and Waring, C.A. (1918), Manganese and chromium in California: California Mining Bureau. Bulletin 76: 177-178.
Allen, John Elliot (1941) Geologic Investigation of the Chromite Deposits of California. California Journal of Mines and Geology, 37 (1). 101-167p.140
Smith, Clay Taylor & A.B. Griggs (1944), Chromite deposits near San Luis Obispo, San Luis Obispo County, California: USGS Bulletin 945-B: pp. i-iv, 36-37.
Walker, G.W. & .B. Griggs (1953), Chromite deposits of the southern Coast Ranges of California: California Division of Mines Bulletin 134, part 2, chapter 2: 48, 67.
Stinson, Melvin Clarence (1975) California Division of Mining and Geology Mineral Property Report (unpublished).
Pemberton, H. Earl (1983) Minerals of California. Van Nostrand Reinhold Company Inc.
Carlson, C.A., et al (1985), Analyses for Platinum-Group Elements in Samples from Podiform Chromite Deposits, California and Oregon: USGS Open-File Report 85-442, 14 p.
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