Mineral Evolution Database
Created and maintained by the Mineral Evolution Project in partnership with RRUFF and mindat.
Mineral locality data provided by mindat.org

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The Mineral Evolution database is currently under development.

The goal of this page is to present localities at which the mineral is found, and estimates of the oldest possible geologic age of the minerals at these localities.


Locality Name:
Humphreys Station, Big Dry Creek District, Fresno Co., California, USA

Oldest recorded age at locality: 483
Youngest recorded age at locality: 483

mindat Locality ID: 217471
mindat URL: http://www.mindat.org/loc-217471.html

Tectonic Settings:

Total number of sublocalities beneath "Humphreys Station, Big Dry Creek District, Fresno Co., California, USA": 30
Total number of bottom-level sublocalities: 30

Number of Child Localities: 30
Child Localities:
Alice Mine (Partridge Mine)
B. B. Mine
Big Bertha Mine
Black Bow Mine (Strassbaugh; Black Bow Avery Prospect)
Black Mountain Prospect
Camden Mine
Clara H Mine (Clara H. Mine & Mill)
Dolly Varden Mine
Ely And Gibons Mine
Erickson Mine
Jack Thorn Mine (Thorn Mine [?])
John Burnett Mine
Kirkland Lease Mine
Lacey Mine
Lava Mine (Little Oak Mine)
Letty And Lotty Claims
Lucky Boy Mine
Manchester Mine (Manchester Extension Mine; Side Kicker Mine)
Neiper Mine (Nieper Mine; Kneiper Mine)
Old Dollie Occurrence
Rock Wren Mine (Serpentine)
Ross Occurrence
Saint Mine
Sunset Mine [1]
Unidentified Cr Mine [15]
Union Occurrence
Unnamed Cr Mine [14]
Unnamed Cr Occurrence [3]
Unnamed Talc Occurrence [2]
Victor Mine

Latitude: 36°56'50"N
Longitude: 119°25'20"W
Decimal Degree (lat, lon): 36.947222222222,-119.42222222222

AThis mineral is Anthropogenic.
GThis mineral is directly dated.
BThis mineral is reported as having this age.
YThis mineral is using an age reported as an element mineralization period.
OThis mineral is using an age calculated from all data at the locality.
RThe age displayed for this mineral originates from a different, non-child locality.
PThe age displayed for this mineral is the range of ages for this mineral at all of this locality's children.
This mineral's age has not yet been recorded.

This Mineral list contains entries from this locality, including sub-localities. Minerals in bold are reported by mindat.org as occurring directly at this locality, and do not occur at any children (sublocalities) of this locality.

Elements at this locality, including sub-localities: Al C Cr Cu Fe H Mg O S Si 

Elements from minerals reported directly at this locality: 

Structural Groups for minerals in this locality: 
CalciteChalcanthiteChalcopyriteChloriteClayNoneSmectite-vermiculiteSpinelTalc

8 IMA Minerals at location:
Chalcanthite  (*)Chalcopyrite  (*)Chromite  (*)Clinochlore  (*)Magnesiochromite  (*)
Magnesite  (*)Talc  (*)Vermiculite  (*)
Mineral nameStructural GroupsIMA FormulaMax Age (Ma)Min Age (Ma)# of Sublocalities containing mineralLOCALITY IDs, not mindat ids# of localities containing mineral
Chalcanthite  (*)ChalcanthiteCu(SO4)·5H2O1155556925
Chalcopyrite  (*)ChalcopyriteCuFeS2115555627198
Chromite  (*)SpinelFe2+Cr2O44834834155541,155550,155562,1555673902
Clinochlore  (*)Chlorite ClayMg5Al(AlSi3O10)(OH)811555661756
Magnesiochromite  (*)SpinelMgCr2O44834832155544,155551311
Magnesite  (*)CalciteMg(CO3)48348311555441487
Talc  (*)Clay TalcMg3Si4O10(OH)211555663337
Vermiculite  (*)Clay Smectite-vermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4·8H2O1155566652



13 Ages assigned to this locality:

Excel IDMax Age (Ma)Min Age (Ma)Age as listed in referenceDating MethodAge InterpretPrioritized?Sample SourceSample NumRun NumAge from other LocalityDated MineralMinerals explicitely stated as having this ageAge applies to these ElementsMinDat Locality IDDated Locality (Max Age)Location as listed in referenceReferenceReference DOIReference IDAge Notes
podchrome-00027483483Lower Ordovician (483±21 Ma Sm-Nd whole rock and mineral)       Cr76235Alice Mine (Partridge Mine), Humphreys Station, Big Dry Creek District, Fresno Co., California, USAAliceMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00030483483Lower Ordovician (483±21 Ma Sm-Nd whole rock and mineral)       Cr76261Black Bow Mine (Strassbaugh; Black Bow Avery Prospect), Humphreys Station, Big Dry Creek District, Fresno Co., California, USABlack BowMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00031483483Lower Ordovician (483±21 Ma Sm-Nd whole rock and mineral)       Cr76261Black Bow Mine (Strassbaugh; Black Bow Avery Prospect), Humphreys Station, Big Dry Creek District, Fresno Co., California, USABlack BowMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00035483483Lower Ordovician (483±21 Ma Sm-Nd whole rock and mineral)       Cr76277Camden Mine, Humphreys Station, Big Dry Creek District, Fresno Co., California, USACamdenMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00038483483Lower Ordovician (483±21 Ma Sm-Nd whole rock and mineral)       Cr76281Clara H Mine (Clara H. Mine & Mill), Humphreys Station, Big Dry Creek District, Fresno Co., California, USAClara HMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00040483483Lower Ordovician (483±21 Ma Sm-Nd whole rock and mineral)       Cr76312Erickson Mine, Humphreys Station, Big Dry Creek District, Fresno Co., California, USAEricksonMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00033483483Lower Ordovician (483±21 Ma Sm-Nd whole rock and mineral)       Cr76382Lacey Mine, Humphreys Station, Big Dry Creek District, Fresno Co., California, USALaceyMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00037483483Lower Ordovician (483±21 Ma Sm-Nd whole rock and mineral)       Cr76386Letty And Lotty Claims, Humphreys Station, Big Dry Creek District, Fresno Co., California, USALetty and Lotty ClaimsMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00029483483Lower Ordovician (483±21 Ma Sm-Nd whole rock and mineral)       Cr76404Lucky Boy Mine, Humphreys Station, Big Dry Creek District, Fresno Co., California, USALucky BoyMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00036483483Lower Ordovician (483±21 Ma Sm-Nd whole rock and mineral)       Cr76405Manchester Mine (Manchester Extension Mine; Side Kicker Mine), Humphreys Station, Big Dry Creek District, Fresno Co., California, USAManchesterMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00028483483Lower Ordovician (483±21 Ma Sm-Nd whole rock and mineral)       Cr76475Rock Wren Mine (Serpentine), Humphreys Station, Big Dry Creek District, Fresno Co., California, USARock WrenMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00039483483Lower Ordovician (483±21 Ma Sm-Nd whole rock and mineral)       Cr76488Saint Mine, Humphreys Station, Big Dry Creek District, Fresno Co., California, USASaintMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00034483483Lower Ordovician (483±21 Ma Sm-Nd whole rock and mineral)       Cr76509Sunset Mine [1], Humphreys Station, Big Dry Creek District, Fresno Co., California, USASunsetMoiser et al. (2012) USGSSIR2012_5157 


SampleSource LocalityReference URL


All locality data graciously provided by mindat.org

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