Mineral Evolution Database

Created and maintained by the Mineral Evolution Project in partnership with RRUFF and mindat.

Mineral locality data provided by mindat.org

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:
Coloma, Coloma District, West Belt, El Dorado Co., California, USA

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

mindat Locality ID: 212994
mindat URL: http://www.mindat.org/loc-212994.html

Tectonic Settings:

Total number of sublocalities beneath "Coloma, Coloma District, West Belt, El Dorado Co., California, USA": 32
Total number of bottom-level sublocalities: 31

Number of Child Localities: 29
Child Localities:
Bona Forsa Mine
Caledonia Mine
Daniel McGee Claim
Endriss Placer
Eureka Placer
Hummingbird Ranch
Irish Creek Falls Placer
Laicy Claim
Last Chance Mine [2]
Matherly Dredge
McCurdy Mine [2]
North Extension Rocky Bend Mine
O'Brien Mine (S-Bend Mine)
Pleasant Flat Placer
Russian American Mine
Sailor Flat And Irish Creek Placer
Schreiber Dredge
Shelley Mine (Wolf Mine; Shelly Mine; Shelley Wolf Mine)
Sheppard Mine
Simon Mine
Standard Mine
Stuckslager Mine (Stuckslacker Mine; Sam Simms Mine)
Sutter Mill Bar And River (Old Sutter Mill Site)
Sutter Mill Bar And River Placer (Old Sutter Mill Site)
Swansea And Rocky Bend Mine
Tropper Occurrence
U. S. Hydraulic Occurrence
Unspecified Au Occurrence [1]
Unspecified Cr Occurrence [1]

Latitude: 38°49'6"N
Longitude: 120°52'52"W
Decimal Degree (lat, lon): 38.818333333333,-120.88111111111

A	This mineral is Anthropogenic.
G	This mineral is directly dated.
B	This mineral is reported as having this age.
Y	This mineral is using an age reported as an element mineralization period.
O	This mineral is using an age calculated from all data at the locality.
R	The age displayed for this mineral originates from a different, non-child locality.
P	The 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.

Calcite	Chlorite	Clay	Copper	Corundum	Mica	Nickeline	None	Olivine	Pentlandite
Pyroxene	Quartz	Rocksalt	Serpentine	Sphalerite	Spinel	Talc	Tochilinite

Calcite ()*	Chromite ()*	Clinochlore ()*	Corundum ()*	Cronstedtite ()*
Diopside ()*	Dolomite ()*	Enstatite ()*	Forsterite ()*	Gold ()*
Hedenbergite ()*	Magnesiochromite ()*	Magnetite ()*	Oldhamite ()*	Pentlandite ()*
Pyrrhotite ()*	Quartz ()*	Roscoelite ()*	Schreibersite ()*	Sphalerite ()*
Spinel ()*	Talc ()*	Tochilinite ()*	Troilite ()*

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 Au C Ca Cr Fe H K Mg Ni O P S Si V Zn

Elements from minerals reported directly at this locality:

Structural Groups for minerals in this locality:
Calcite Chlorite Clay Copper Corundum Mica Nickeline None Olivine Pentlandite
Pyroxene Quartz Rocksalt Serpentine Sphalerite Spinel Talc Tochilinite

24 IMA Minerals at location:

Mineral name	Structural Groups	IMA Formula	Max Age (Ma)	Min Age (Ma)	# of Sublocalities containing mineral	LOCALITY IDs, not mindat ids	# of localities containing mineral
Calcite ()*	Calcite	Ca(CO₃)			1	155309	27770
Chromite ()*	Spinel	Fe²⁺Cr₂O₄	388	388	8	155292,155295,155297,155303,155304,155309,155313,155316	3902
Clinochlore ()*	Chlorite Clay	Mg₅Al(AlSi₃O₁₀)(OH)₈	388	388	1	155302	1756
Corundum ()*	Corundum	Al₂O₃			1	155309	1797
Cronstedtite ()*	Clay Serpentine	(Fe²⁺,Fe³⁺)₃(Si,Fe³⁺)₂O₅(OH)₄			1	155309	54
Diopside ()*	Pyroxene	CaMgSi₂O₆			1	155309	4135
Dolomite ()*	None	CaMg(CO₃)₂			1	155309	9895
Enstatite ()*	Pyroxene	Mg₂Si₂O₆			1	155309	944
Forsterite ()*	Olivine	Mg₂(SiO₄)			1	155309	1188
Gold ()*	Copper	Au			13	155286,155293,155294,155296,155299,155301,155305,155306,155308,155310,155311,155312,155315	30554
Hedenbergite ()*	Pyroxene	CaFe²⁺Si₂O₆			1	155309	741
Magnesiochromite ()*	Spinel	MgCr₂O₄	388	388	1	155302	311
Magnetite ()*	Spinel	Fe²⁺Fe³⁺₂O₄			1	155309	14899
Oldhamite ()*	Rocksalt	CaS			1	155309	58
Pentlandite ()*	Pentlandite	(Ni,Fe)₉S₈			1	155309	1512
Pyrrhotite ()*	Nickeline	Fe₇S₈			1	155309	9056
Quartz ()*	Quartz	SiO₂			7	155286,155293,155296,155299,155305,155306,155312	61156
Roscoelite ()*	Mica	KV³⁺₂(Si₃Al)O₁₀(OH)₂			2	155306,155308	253
Schreibersite ()*	None	(Fe,Ni)₃P			1	155309	374
Sphalerite ()*	Sphalerite	ZnS			1	155309	21482
Spinel ()*	Spinel	MgAl₂O₄			1	155309	1934
Talc ()*	Clay Talc	Mg₃Si₄O₁₀(OH)₂	388	388	3	155295,155297,155302	3337
Tochilinite ()*	Tochilinite	6(Fe_0.9S)·5[(Mg,Fe)(OH)₂]			1	155309	56
Troilite ()*	None	FeS			1	155309	1044

6 Ages assigned to this locality:

Excel ID	Max Age (Ma)	Min Age (Ma)	Age as listed in reference	Age applies to these Elements	MinDat Locality ID	Dated Locality (Max Age)	Location as listed in reference	Reference	Reference ID
podchrome-00119	388	388	pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)	Cr	77910	McCurdy Mine [2], Coloma, Coloma District, West Belt, El Dorado Co., California, USA	McCurdy	Moiser et al. (2012)	USGSSIR2012_5157
podchrome-00120	388	388	pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)	Cr	77999	O'Brien Mine (S-Bend Mine), Coloma, Coloma District, West Belt, El Dorado Co., California, USA	O'Brien	Moiser et al. (2012)	USGSSIR2012_5157
podchrome-00123	388	388	pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)	Cr	78187	Shelley Mine (Wolf Mine; Shelly Mine; Shelley Wolf Mine), Coloma, Coloma District, West Belt, El Dorado Co., California, USA	Shelly	Moiser et al. (2012)	USGSSIR2012_5157
podchrome-00125	388	388	pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)	Cr	78190	Sheppard Mine, Coloma, Coloma District, West Belt, El Dorado Co., California, USA	Sheppard	Moiser et al. (2012)	USGSSIR2012_5157
podchrome-00121	388	388	pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)	Cr	78196	Simon Mine, Coloma, Coloma District, West Belt, El Dorado Co., California, USA	Simon North	Moiser et al. (2012)	USGSSIR2012_5157
podchrome-00122	388	388	pre-Early Devonian-Jurassic (388±17 Ma U-Pb zircon from felsic igneous rocks; 174 Ma K-Ar white mica from blueschists)	Cr	78196	Simon Mine, Coloma, Coloma District, West Belt, El Dorado Co., California, USA	Simon South	Moiser et al. (2012)	USGSSIR2012_5157

Sample	Source Locality	Reference URL

All locality data graciously provided by mindat.org

All age data...