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Unnamed Cr occurrence [1], Upper Crystal Springs Reservoir (Crystal Springs Lake), San Mateo, San Mateo County, California, USAi
Regional Level Types
Unnamed Cr occurrence [1]Occurrence
Upper Crystal Springs Reservoir (Crystal Springs Lake)Reservoir
San MateoCity
San Mateo CountyCounty
CaliforniaState
USACountry

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Latitude & Longitude (WGS84):
37° 30' 15'' North , 122° 20' 42'' West
Latitude & Longitude (decimal):
37.50443,-122.34521
GRN:
N26W69
Type:
Occurrence
Köppen climate type:
Csb : Warm-summer Mediterranean climate
Nearest Settlements:
PlacePopulationDistance
Highlands-Baywood Park4,027 (2011)2.0km
Belmont27,218 (2017)6.4km
San Mateo103,536 (2017)6.7km
San Carlos29,931 (2017)7.5km
Emerald Lake Hills4,278 (2011)8.1km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Sequoia Gem and Mineral SocietyRedwood City, California10km
Peninsula Gem & Geology Society, Inc.Los Altos, California24km
East Bay Mineral and Lapidary ClubHayward, California29km
Mineral & Gem Society of Castro ValleyHayward, California30km
San Francisco Gem and Mineral Society, Inc.San Francisco, California31km
Mindat Locality ID:
215169
Long-form identifier:
mindat:1:2:215169:7
GUID (UUID V4):
0


An unnamed Cr occurrence located near Crystal Springs Lakes W of San Mateo, on the Pacific coast.

NOTE: Crystal Springs Lake are actually 2 reservoirs (lower & upper) which straddle the San Andreas Fault rift. Available data do not indicate which is closer to this occurrence.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


1 valid mineral.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘChromite4.BB.05Fe2+Cr3+2O4
Unclassified
ⓘ'Serpentine Subgroup'-D3[Si2O5](OH)4

List of minerals for each chemical element

HHydrogen
Hⓘ Serpentine SubgroupD3[Si2O5](OH)4
OOxygen
Oⓘ ChromiteFe2+Cr23+O4
Oⓘ Serpentine SubgroupD3[Si2O5](OH)4
SiSilicon
Siⓘ Serpentine SubgroupD3[Si2O5](OH)4
CrChromium
Crⓘ ChromiteFe2+Cr23+O4
FeIron
Feⓘ ChromiteFe2+Cr23+O4

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

Hanks, Henry Garber (1884), Fourth report of the State Mineralogist: California Mining Bureau. Report 4, 410 pp. (includes catalog of minerals of California pp. 63-410), and miscellaneous observations on mineral products): 137.
Huguenin, Emile & W.O. Castello (1921), Alameda, Contra Costa, San Francisco, San Mateo, Santa Clara, Santa Cruz Counties: California Mining Bureau. Report 17: 172
Murdoch, Joseph; Webb, Robert Wallace (1966) Minerals of California, Centennial Volume (1866-1966) - California Division of Mines and Geology, Bulletin 189. California Division of Mines and Geology. 559 pp.
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