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 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:
Forest Hill Divide Area, Placer Co., California, USA

Oldest recorded age at locality: 388
Youngest recorded age at locality: 388

mindat Locality ID: 266549
mindat URL: http://www.mindat.org/loc-266549.html

Tectonic Settings:

Total number of sublocalities beneath "Forest Hill Divide Area, Placer Co., California, USA": 73
Total number of bottom-level sublocalities: 71

Number of Child Localities: 2
Child Localities:
Hughes Mill
Sugar Pine Reservoir

Latitude: 39°7'13"N
Longitude: 120°46'16"W
Decimal Degree (lat, lon): 39.120277777778,-120.77111111111

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: Au C Ca Cr Fe H Mg O Si 

Elements from minerals reported directly at this locality: 

Structural Groups for minerals in this locality: 
CalciteClayCopperGarnetNoneQuartzSerpentineSpinelTalc

9 IMA Minerals at location:
Antigorite  (*)Chromite  (*)Dolomite  (*)Gold  (*)Magnesiochromite  (*)
Magnesite  (*)Quartz  (*)Talc  (*)Uvarovite  (*)
Mineral nameStructural GroupsIMA FormulaMax Age (Ma)Min Age (Ma)# of Sublocalities containing mineralLOCALITY IDs, not mindat ids# of localities containing mineral
Antigorite  (*)Serpentine ClayMg3Si2O5(OH)41167070708
Chromite  (*)SpinelFe2+Cr2O438838863167058,167059,167060,167061,167062,167064,167065,167067,167068,167069,167070,167071,167072,167073,167074,167075,167076,167077,167078,167079,167080,167082,167083,167086,167087,167088,167089,167090,167091,167092,167093,167094,167095,167096,167098,167099,167100,167101,167102,167103,167105,167106,167108,167109,167110,167111,167112,167113,167114,167115,167116,167117,167118,167119,167121,167122,167123,167124,167125,167126,167127,167128,1671293902
Dolomite  (*)NoneCaMg(CO3)211670709895
Gold  (*)CopperAu116710430554
Magnesiochromite  (*)SpinelMgCr2O43883881167063311
Magnesite  (*)CalciteMg(CO3)11670701487
Quartz  (*)QuartzSiO2116710461156
Talc  (*)Clay TalcMg3Si4O10(OH)211671043337
Uvarovite  (*)GarnetCa3Cr2(SiO4)33883881167109212



14 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-00145388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85107Blue Bell And Bee Bee Claims (Blue Bell & Bee Bee Claims), Hughes Mill, Forest Hill Divide Area, Placer Co., California, USABlue Bell and Bee Bee ClaimsMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00139388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85121Boiler Pit Mine (Victory Chrome Company Deposit; Sugar Pine Chrome Mines), Hughes Mill, Forest Hill Divide Area, Placer Co., California, USABoiler PitMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00144388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85161Buzzard And Blue Jay Claims (Buzzard & Blue Jay), Hughes Mill, Forest Hill Divide Area, Placer Co., California, USABuzzard and Blue Jay ClaimsMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00141388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85315Esther And Phyllis Mine (Esther & Phyllis), Hughes Mill, Forest Hill Divide Area, Placer Co., California, USAEsther and PhyllisMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00148388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85411Green's Capco Leases Mine (Greens Capco), Hughes Mill, Forest Hill Divide Area, Placer Co., California, USAGreen's CAPCO (NE Section 32)Moiser et al. (2012) USGSSIR2012_5157 
podchrome-00149388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85411Green's Capco Leases Mine (Greens Capco), Hughes Mill, Forest Hill Divide Area, Placer Co., California, USAGreen's CAPCO (NE Section 31)Moiser et al. (2012) USGSSIR2012_5157 
podchrome-00138388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85530Long Pit & Yellow Pit Deposits (Long Pit; Yellow Pit Deposits), Hughes Mill, Forest Hill Divide Area, Placer Co., California, USAYellow PitMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00146388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85551Maralls' Capco Leases Mine (Maralls Capco Leases), Hughes Mill, Forest Hill Divide Area, Placer Co., California, USACAPCO (NE)Moiser et al. (2012) USGSSIR2012_5157 
podchrome-00147388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85551Maralls' Capco Leases Mine (Maralls Capco Leases), Hughes Mill, Forest Hill Divide Area, Placer Co., California, USACAPCO (SE)Moiser et al. (2012) USGSSIR2012_5157 
podchrome-00142388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85687Port Wine Mine, Hughes Mill, Forest Hill Divide Area, Placer Co., California, USADart and Braden (Section 30)Moiser et al. (2012) USGSSIR2012_5157 
podchrome-00143388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85687Port Wine Mine, Hughes Mill, Forest Hill Divide Area, Placer Co., California, USADart and Braden (Section 31)Moiser et al. (2012) USGSSIR2012_5157 
podchrome-00137388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85711Randall Claims Nos. 1 & 2, Hughes Mill, Forest Hill Divide Area, Placer Co., California, USARandall ClaimsMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00151388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85798Southern Pacific Property (Gore; Garrison; G.H.; Muller And Mathews Lease; Fitgerald And Russel Lease; Lookout; Bell Occurrence; King Occurrence), Hughes Mill, Forest Hill Divide Area, Placer Co., California, USASouthern Pacific (east workings)Moiser et al. (2012) USGSSIR2012_5157 
podchrome-00150388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85824Sunset Mine (Sun Set Chrome Mine; Sugar Pine Chrome Mine), Hughes Mill, Forest Hill Divide Area, Placer Co., California, USASunsetMoiser et al. (2012) USGSSIR2012_5157 


SampleSource LocalityReference URL


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