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:
Placer Co., California, USA

Oldest recorded age at locality: 388
Youngest recorded age at locality: 3.5

mindat Locality ID: 7857
mindat URL: http://www.mindat.org/loc-7857.html

Tectonic Settings:

Total number of sublocalities beneath "Placer Co., California, USA": 1197
Total number of bottom-level sublocalities: 1076

Number of Child Localities: 37
Child Localities:
American River
Bald Rock Mountain
Canada Hill District
Cisco
Clipper Gap
Colfax District (Illinois District)
Damascus District (Sunny South District)
Duncan Peak District
Dutch Flat District (Towle District)
East Belt
Emigrant Gap District (Blue Canyon District)
Forest Hill District
Forest Hill Divide Area
George Slide Mine
Gold Run District
Grizzly Bear House
Hotaling
Iowa Hill District
Last Chance District
Lincoln District
Magra
Marshall Canyon
Michigan Bluff District (Michigan Bluff Deposit)
Midas
Ophir District (Auburn District; Duncan Hill District)
Oro Flame Mine
Penryn District
Ralston Divide District
Rocklin District (Loomis District)
Roseville
Scotts Corner
Snakehead Point
Sugarloaf
Tahoe District
Unnamed Magnesite Occurrences [2]
Westville District
Wheatland District

Latitude: 39°3'14"N
Longitude: 120°51'41"W
Decimal Degree (lat, lon): 39.053888888889,-120.86138888889
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: Ag Al As Au B C Ca Cl Co Cr Cu F Fe H K Mg Mn Mo Na Ni O Os Pb Pt S Sb Si Th Ti W Zn Zr 

Elements from minerals reported directly at this locality: C H Mn O Si 

Structural Groups for minerals in this locality: 
AcanthiteAmorphousAmphiboleArsenopyriteBrookiteCalciteChalcanthiteChalcopyriteChloriteClay
ClinozoisiteCobaltiteCopperCoquimbiteCorundumDiamondEpidoteFeldsparGarnetKaolinite
MalachiteMarcasiteMicaMilleriteMolybdeniteNoneNot in a structural groupPyritePyroxeneQuartz
RhodoniteRocksaltRutileScheeliteSerpentineSmectite-vermiculiteSphaleriteSpinelStibniteTalc
TetrahedriteTourmalineVesuvianiteZircon

69 IMA Minerals at location:
Acanthite  (*)Albite  (*)Alunogen  (*)Ankerite  (*)Anthophyllite  (*)
Antigorite  (*)Arsenopyrite  (*)Azurite  (*)Brookite  (*)Calcite  (*)
Chalcanthite  (*)Chalcocite  (*)Chalcopyrite  (*)Chlorargyrite  (*)Chromite  (*)
Chrysotile  (*)Clinochlore  (*)Cobaltite  (*)Copper  (*)Coquimbite  (*)
Cuprite  (*)Diamond  (*)Diopside  (*)Dolomite  (*)Epidote  (*)
Galena  (*)Gold  (*)Graphite  (*)Grossular  (*)Hausmannite  (*)
Hematite  (*)Hercynite  (*)Ilmenite  (*)Kalinite  (*)Kaolinite  (*)
Lechatelierite  (*)Magnesiochromite  (*)Magnesite  (*)Magnetite  (*)Malachite  (*)
Manganite  (*)Marcasite  (*)Millerite  (*)Molybdenite  (*)Muscovite  (*)
Nontronite  (*)Opal  (*)Osmium  (*)Platinum  (*)Pyrargyrite  (*)
Pyrite  (*)Pyrolusite  (*)Quartz  (*)Rhodochrosite  (*)Rhodonite  (*)
Rutile  (*)Scheelite  (*)Schorl  (*)Siderite  (*)Silver  (*)
Sphalerite  (*)Stibnite  (*)Talc  (*)Tetrahedrite-(Zn)  (*)Thorite  (*)
Tremolite  (*)Uvarovite  (*)Vesuvianite  (*)Zircon  (*)
Mineral nameStructural GroupsIMA FormulaMax Age (Ma)Min Age (Ma)# of Sublocalities containing mineralLOCALITY IDs, not mindat ids# of localities containing mineral
Acanthite  (*)AcanthiteAg2S2167523,1676142793
Albite  (*)FeldsparNa(AlSi3O8)11674908803
Alunogen  (*)Not in a structural groupAl2(SO4)3(H2O)12·5H2O1167804272
Ankerite  (*)NoneCa(Fe2+,Mg)(CO3)23166958,166982,1674903092
Anthophyllite  (*)Amphibole   Mg2Mg5Si8O22(OH)21167723718
Antigorite  (*)Serpentine ClayMg3Si2O5(OH)43883882167070,167458708
Arsenopyrite  (*)ArsenopyriteFeAsS3881325166627,166656,166659,166838,1674959052
Azurite  (*)Not in a structural groupCu3(CO3)2(OH)21701702166622,1678125509
Brookite  (*)BrookiteTiO21167633700
Calcite  (*)CalciteCa(CO3)132132116749527770
Chalcanthite  (*)ChalcanthiteCu(SO4)·5H2O1701701167812925
Chalcocite  (*)NoneCu2S17017011678125707
Chalcopyrite  (*)ChalcopyriteCuFeS217013225166623,166640,166663,166685,166703,166705,166751,167177,167179,167494,167495,167497,167501,167506,167519,167523,167530,167578,167590,167595,167614,167752,167802,167803,16781227198
Chlorargyrite  (*)RocksaltAgCl2167396,1676181382
Chromite  (*)SpinelFe2+Cr2O4388204110166620,166671,166693,166698,166720,166725,166775,166847,166852,166855,166863,166864,166867,166868,166870,166888,166939,166940,166942,166944,166946,166949,166953,166955,166970,166971,166999,167003,167004,167011,167014,167015,167058,167059,167060,167061,167062,167064,167065,167067,167068,167069,167070,167071,167072,167073,167074,167075,167076,167077,167078,167079,167080,167082,167083,167086,167087,167088,167089,167090,167091,167092,167093,167094,167095,167096,167098,167099,167100,167101,167102,167103,167105,167106,167108,167109,167110,167111,167112,167113,167114,167115,167116,167117,167118,167119,167121,167122,167123,167124,167125,167126,167127,167128,167129,167173,167178,167186,167310,167444,167462,167463,167471,167565,167717,167722,167724,167730,167731,1677373902
Chrysotile  (*)Serpentine ClayMg3Si2O5(OH)43167228,167265,167739951
Clinochlore  (*)Chlorite ClayMg5Al(AlSi3O10)(OH)84166855,166888,167565,1677301756
Cobaltite  (*)CobaltiteCoAsS2166656,167494966
Copper  (*)CopperCu1701703166622,167591,1678123846
Coquimbite  (*)CoquimbiteAlFe3(SO4)6(H2O)12·6H2O1701702167378,167812136
Cuprite  (*)Not in a structural groupCu2O17017011678122970
Diamond  (*)DiamondC1166991697
Diopside  (*)PyroxeneCaMgSi2O611677484135
Dolomite  (*)NoneCaMg(CO3)23167070,167465,1676339895
Epidote  (*)Epidote ClinozoisiteCa2(Al2Fe3+)[Si2O7][SiO4]O(OH)4166740,167131,167181,1677458173
Galena  (*)RocksaltPbS17017035166630,166635,166636,166641,166685,166734,166750,166751,166763,166800,166875,167340,167453,167495,167499,167503,167507,167509,167518,167519,167523,167530,167532,167533,167572,167578,167583,167588,167595,167598,167609,167614,167617,167618,16781224243
Gold  (*)CopperAu170170388166622,166630,166631,166634,166635,166636,166637,166639,166640,166641,166642,166643,166647,166648,166670,166673,166685,166688,166692,166696,166697,166702,166704,166705,166706,166707,166709,166713,166714,166715,166716,166717,166718,166719,166723,166724,166726,166727,166732,166734,166735,166736,166739,166740,166743,166744,166745,166746,166747,166748,166750,166751,166755,166757,166759,166762,166763,166770,166780,166783,166788,166795,166798,166799,166800,166801,166806,166814,166826,166827,166833,166845,166846,166875,166878,166879,166880,166882,166892,166895,166900,166905,166909,166910,166911,166913,166914,166916,166918,166926,166937,166950,166952,166957,166958,166960,166963,166964,166965,166967,166972,166974,166982,166983,166986,166992,166993,166996,166997,167000,167006,167007,167008,167012,167019,167020,167021,167022,167023,167025,167026,167031,167042,167044,167051,167104,167130,167131,167133,167135,167137,167138,167139,167140,167144,167146,167147,167148,167149,167150,167151,167154,167157,167158,167159,167160,167162,167166,167171,167181,167183,167184,167185,167187,167188,167189,167190,167191,167195,167198,167199,167204,167205,167206,167208,167212,167218,167219,167224,167226,167235,167237,167238,167241,167242,167243,167248,167249,167250,167251,167252,167257,167258,167262,167265,167266,167268,167269,167271,167276,167282,167284,167285,167288,167295,167299,167304,167305,167306,167316,167326,167329,167331,167332,167333,167334,167335,167336,167339,167340,167341,167354,167365,167370,167371,167372,167374,167375,167376,167385,167386,167388,167389,167393,167397,167399,167405,167409,167412,167413,167414,167415,167419,167420,167428,167431,167438,167439,167448,167453,167454,167457,167464,167465,167467,167470,167473,167477,167484,167487,167488,167490,167495,167497,167499,167500,167503,167504,167505,167506,167507,167508,167509,167510,167511,167512,167513,167514,167515,167516,167517,167518,167519,167520,167521,167523,167524,167525,167527,167528,167530,167532,167533,167535,167540,167541,167542,167545,167546,167553,167554,167555,167557,167559,167560,167562,167566,167567,167569,167571,167572,167574,167575,167576,167577,167578,167579,167580,167582,167583,167584,167586,167587,167588,167589,167591,167592,167595,167596,167597,167598,167599,167600,167602,167603,167604,167605,167607,167608,167609,167610,167611,167614,167615,167617,167618,167621,167623,167628,167637,167638,167639,167640,167655,167656,167657,167658,167659,167660,167664,167666,167667,167668,167670,167672,167676,167678,167698,167701,167702,167703,167704,167708,167709,167711,167725,167738,167752,167759,167766,167768,167769,167770,167771,167782,167783,167784,167788,167789,167790,167799,167802,167803,167806,167810,167813,167815,16781630554
Graphite  (*)NoneC2166982,1674682812
Grossular  (*)GarnetCa3Al2(SiO4)311677431544
Hausmannite  (*)SpinelMn2+Mn3+2O41321321167496350
Hematite  (*)CorundumFe2O33166620,167175,16763314640
Hercynite  (*)SpinelFe2+Al2O41167675407
Ilmenite  (*)CorundumFe2+Ti4+O34166620,166740,167131,1671815433
Kalinite  (*)NoneKAl(SO4)2·11H2O1321322167378,16749654
Kaolinite  (*)Clay KaoliniteAl2Si2O5(OH)41701703167368,167381,1678125591
Lechatelierite  (*)AmorphousSiO23883.5062
Magnesiochromite  (*)SpinelMgCr2O43883883166862,167063,167458311
Magnesite  (*)CalciteMg(CO3)10166767,166851,166858,166902,166903,167070,167141,167283,167727,1677721487
Magnetite  (*)SpinelFe2+Fe3+2O43883117166620,166740,167011,167131,167175,167181,16745814899
Malachite  (*)MalachiteCu2(CO3)(OH)21321326166622,166623,167177,167179,167501,16759012537
Manganite  (*)RutileMn3+O(OH)1167046770
Marcasite  (*)MarcasiteFeS211675955674
Millerite  (*)MilleriteNiS11666591066
Molybdenite  (*)MolybdeniteMoS23166663,167495,1675115800
Muscovite  (*)Mica ClayKAl2(Si3Al)O10(OH)24167040,167495,167530,16763317380
Nontronite  (*)Clay Smectite-vermiculiteNa0.3Fe3+2(Si,Al)4O10(OH)2·nH2O1166947471
Opal  (*)AmorphousSiO2·nH2O3883.502994
Osmium  (*)NoneOs1166928169
Platinum  (*)CopperPt3166928,167157,167372485
Pyrargyrite  (*)NoneAg3SbS311675531425
Pyrite  (*)PyriteFeS217013262166620,166630,166635,166636,166640,166643,166647,166648,166685,166692,166705,166713,166714,166715,166719,166726,166734,166736,166740,166751,166801,167131,167155,167176,167177,167181,167340,167453,167465,167490,167495,167500,167501,167503,167506,167517,167519,167523,167528,167530,167533,167546,167574,167575,167578,167584,167588,167590,167591,167595,167605,167608,167609,167614,167617,167618,167633,167752,167769,167784,167803,16781239462
Pyrolusite  (*)RutileMnO24166737,167040,167046,1670473106
Quartz  (*)QuartzSiO2170132207166630,166635,166636,166637,166639,166640,166641,166642,166643,166647,166648,166673,166680,166685,166692,166704,166705,166713,166714,166715,166716,166717,166718,166719,166723,166724,166726,166727,166732,166734,166735,166736,166739,166740,166743,166744,166745,166746,166747,166748,166750,166751,166755,166757,166759,166763,166788,166799,166800,166801,166875,166882,166910,166911,166914,166916,166918,166926,166957,166958,166960,166963,166964,166982,166984,166986,166992,166993,166997,167000,167008,167012,167020,167025,167026,167046,167104,167131,167138,167139,167144,167147,167148,167149,167154,167155,167158,167159,167181,167184,167242,167243,167252,167262,167284,167305,167329,167332,167335,167339,167340,167341,167365,167385,167397,167414,167419,167420,167431,167453,167457,167464,167465,167477,167484,167487,167488,167490,167495,167497,167499,167501,167503,167505,167506,167507,167508,167509,167510,167511,167512,167513,167514,167515,167516,167517,167518,167519,167521,167523,167528,167530,167531,167532,167533,167535,167540,167542,167545,167546,167554,167555,167557,167559,167560,167569,167571,167572,167575,167576,167577,167578,167580,167582,167583,167584,167586,167587,167588,167589,167591,167592,167595,167596,167597,167598,167599,167600,167602,167603,167604,167605,167607,167608,167609,167610,167614,167618,167623,167633,167639,167666,167738,167752,167759,167768,167769,167770,167771,167782,167783,167784,167788,167789,167790,167802,16781261156
Rhodochrosite  (*)CalciteMn(CO3)3883.501711
Rhodonite  (*)RhodoniteCaMn3Mn(Si5O15)3883883166950,167040,167047969
Rutile  (*)RutileTiO22166620,1676335614
Scheelite  (*)ScheeliteCa(WO4)11677564894
Schorl  (*)TourmalineNaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)11676332705
Siderite  (*)CalciteFe(CO3)3166740,167131,1671816417
Silver  (*)CopperAg1701706167378,167495,167500,167591,167618,1678125186
Sphalerite  (*)SphaleriteZnS17017010166641,166751,167495,167519,167522,167523,167591,167595,167617,16781221482
Stibnite  (*)StibniteSb2S32167495,1676093418
Talc  (*)Clay TalcMg3Si4O10(OH)23111706166686,166705,166982,167011,167104,1678123337
Tetrahedrite-(Zn)  (*)TetrahedriteCu6(Cu4Zn2)Sb4S138166715,167378,167495,167511,167520,167574,167579,1675915317
Thorite  (*)ZirconTh(SiO4)11666201006
Tremolite  (*)Amphibole   Ca2(Mg5.0-4.5Fe2+0.0-0.5)Si8O22(OH)211677232562
Uvarovite  (*)GarnetCa3Cr2(SiO4)33883119166855,166862,167014,167109,167186,167458,167565,167730,167737212
Vesuvianite  (*)Vesuvianite(Ca,Na)19(Al,Mg,Fe)13(SiO4)10(Si2O7)4(OH,F,O)1011666581395
Zircon  (*)ZirconZr(SiO4)6166620,166740,166928,167131,167181,1673815251


35 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-00131388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85443Hodge Ranch Occurrence, Alta, Dutch Flat District (Towle District), Placer Co., California, USAHodge Ranch NEMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00132388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85065Beat Claim, Casa Loma, Dutch Flat District (Towle District), Placer Co., California, USABeat ClaimMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00133388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85480Julian Claims, Casa Loma, Dutch Flat District (Towle District), Placer Co., California, USAJulian ClaimsMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00134388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85791Snakehead Claim (Jumbo Claim; Snakebead [typo]), Casa Loma, Dutch Flat District (Towle District), Placer Co., California, USASnakehead ClaimMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00154388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr215876Buttercup Chrome Occurrence, Lehigh Canyon Patent Property (Poco Tiempo Quartz Mine; Buttercup Chrome Occurrence), Bath, Forest Hill District, Placer Co., California, USAButtercup ChromeMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00155388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr215875Poco Tiempo Quartz Mine, Lehigh Canyon Patent Property (Poco Tiempo Quartz Mine; Buttercup Chrome Occurrence), Bath, Forest Hill District, Placer Co., California, USAPoco TiempoMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00153388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85968Washout Claim, Bath, Forest Hill District, Placer Co., California, USAWashout ClaimMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00156388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85103Black Rock Chrome Deposit, Foresthill, Forest Hill District, Placer Co., California, USABlack Rock ChromeMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00158311311Pennsylvanian (304-311 Ma U-Pb zircon from plagiogranite)       Cr85331Fiddler's Green Deposit (Farmer Property), Todd Valley, Forest Hill District, Placer Co., California, USAFiddler's GreenMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00157311311Pennsylvanian (304-311 Ma U-Pb zircon from plagiogranite)       Cr85348Gas Canyon Claim, Todd Valley, Forest Hill District, Placer Co., California, USAGas Canyon ClaimMoiser et al. (2012) USGSSIR2012_5157 
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 
podchrome-00160204204Upper Triassic-Lower Jurassic or older (204±2 Ma U-Pb zircon on leucodiorite)       Cr85096Black Arrow Ranch Deposit, Hotaling, Placer Co., California, USABlack Arrow RanchMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00159204204Upper Triassic-Lower Jurassic or older (204±2 Ma U-Pb zircon on leucodiorite)       Cr85653Parker Ranch Chromite Deposit (McNear Property; Meadowbrook Ranch; Auburn Chrome Mine), Hotaling, Placer Co., California, USAParker RanchMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00152388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85152Bunker Mine (Bunker Mines; Blue Bird Mine [1880's]; Bay Tree Prospect; Sunnyside Occurrence), Sage Hill, Michigan Bluff District (Michigan Bluff Deposit), Placer Co., California, USABunker (main)Moiser et al. (2012) USGSSIR2012_5157 
podchrome-00140388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85600Mountain View Group (Manzanita Chrome Mine [1918]; Victory Chrome Company), Sage Hill, Michigan Bluff District (Michigan Bluff Deposit), Placer Co., California, USAMountain ViewMoiser et al. (2012) USGSSIR2012_5157 
USGS-Rb-Sr-05952132132132Rb-Srage not evaluatedwhole rock     85233Davenport Mine, Auburn, Ophir District (Auburn District; Duncan Hill District), Placer Co., California, USA USGS-Rb-Sr USGS-Rb-Sr 
podchrome-00136388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85616North Fork Chrome Mine, Snakehead Point, Placer Co., California, USANorth Fork ChromeMoiser et al. (2012) USGSSIR2012_5157 
podchrome-00135388388pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)       Cr85975West Chrome Mine (Knob Hill Prospect; West Prospect), Snakehead Point, Placer Co., California, USAWest ChromeMoiser et al. (2012) USGSSIR2012_5157 
NAVDAT-13080763.54.75±1.25   130807    215816Carnelian Bay, Tahoe District, Placer Co., California, USA NAVDAT NAVDAT 
NAVDAT-1308983.973.693.83±0.14   130898    85558Marrs Mine, Westville, Westville District, Placer Co., California, USA NAVDAT NAVDAT 
vms-01028170170Jurassic       S85223Dairy Farm Mine (Trent; Vantrent Mine), Kilaga Springs, Wheatland District, Placer Co., California, USADairy FarmMoiser et al. (2009) USGSOFR2009_1034 
vms-01045170170Jurassic       S85950Valley View Mine (Whiskey Hill Mine; Whiskey Diggings; Whislcey Diggings; Harpening Kilaga Springs; Harpending Mine; Bonanza [?]), Kilaga Springs, Wheatland District, Placer Co., California, USAValley ViewMoiser et al. (2009) USGSOFR2009_1034 

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