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:
Sage Hill, Michigan Bluff District (Michigan Bluff Deposit), Placer Co., California, USA

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

mindat Locality ID: 266370
mindat URL: http://www.mindat.org/loc-266370.html

Tectonic Settings:

Total number of sublocalities beneath "Sage Hill, Michigan Bluff District (Michigan Bluff Deposit), Placer Co., California, USA": 29
Total number of bottom-level sublocalities: 28

Number of Child Localities: 28
Child Localities:
American Bar Mine (American Bar Quartz Mine)
Blanche Placer Mine
Bower Mine
Britt Mine
Bunker And Nihill Mine (Bunker & Nihill; Bunker Hill [?])
Bunker Mine (Bunker Mines; Blue Bird Mine [1880's]; Bay Tree Prospect; Sunnyside Occurrence)
Burnham Pit
Burroughs Tunnel & Burroughs Pit
Clinton Burro Prospects (Chromite)
Cultus Quartz Lode
De Maria Mine (Garbe Mine)
Eagle's Nest Mine (Mystery Wind Mine)
Embree Group
Gorman Placer (Gorman Pit; Gorman Mine)
Hills Armstrong Graphite Deposit
Hoffman Pit (Hoffman Pits; Frank Hoffman)
Mitter Slope Placer Mine
Mountain View Group (Manzanita Chrome Mine [1918]; Victory Chrome Company)
Pleasant Bar Placer
Red Ink Maid Mine
Russel Mine
Sage Hill Deposits
Stoney Bar (Stumps Bar)
Unnamed Au Mine [38]
Unnamed Au Prospect [88]
Unnamed S Occurrence [1]
Volcanoville Deposit
Washburn Mine

Latitude: 39°1'38"N
Longitude: 120°45'29"W
Decimal Degree (lat, lon): 39.027222222222,-120.75805555556

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 Pb S Si 

Elements from minerals reported directly at this locality: 

Structural Groups for minerals in this locality: 
ClayCopperGarnetNonePyriteQuartzRocksaltSerpentineSpinel

11 IMA Minerals at location:
Antigorite  (*)Chromite  (*)Dolomite  (*)Galena  (*)Gold  (*)
Graphite  (*)Magnesiochromite  (*)Magnetite  (*)Pyrite  (*)Quartz  (*)
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)43883881167458708
Chromite  (*)SpinelFe2+Cr2O43883883167462,167463,1674713902
Dolomite  (*)NoneCaMg(CO3)211674659895
Galena  (*)RocksaltPbS116745324243
Gold  (*)CopperAu9167453,167454,167457,167464,167465,167467,167470,167473,16747730554
Graphite  (*)NoneC11674682812
Magnesiochromite  (*)SpinelMgCr2O43883881167458311
Magnetite  (*)SpinelFe2+Fe3+2O4388388116745814899
Pyrite  (*)PyriteFeS22167453,16746539462
Quartz  (*)QuartzSiO25167453,167457,167464,167465,16747761156
Uvarovite  (*)GarnetCa3Cr2(SiO4)33883881167458212



2 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-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 


SampleSource LocalityReference URL


All locality data graciously provided by mindat.org

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