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:
Grau Mine (Gruu Mine), North Elder Creek Group (Joyce Mine; Hill Mine; Noble Electric Steel Company Mine; SW Hill Mine; Elder Creek Mine), Tehama Co., California, USA

Oldest recorded age at locality: 167
Youngest recorded age at locality: 167

mindat Locality ID: 95991
mindat URL: http://www.mindat.org/loc-95991.html

Tectonic Settings: Oceanic Arc (Subduction)

Total number of sublocalities beneath "Grau Mine (Gruu Mine), North Elder Creek Group (Joyce Mine; Hill Mine; Noble Electric Steel Company Mine; SW Hill Mine; Elder Creek Mine), Tehama Co., California, USA": 1
Total number of bottom-level sublocalities: 1

Number of Child Localities: 1
Child Localities:
West Pit (Grau Pit)

Latitude: 40°1'41"N
Longitude: 122°40'18"W
Decimal Degree (lat, lon): 40.028055555556,-122.67166666667

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.

Aragonite	Calcite	Clay	None	Pyroxene	Serpentine	Spinel

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: C Ca Cr Fe H Mg O Si

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

Structural Groups for minerals in this locality:
Aragonite Calcite Clay None Pyroxene Serpentine Spinel

6 IMA Minerals at location:

Antigorite ()*	Aragonite ()*	Chromite ()*	Enstatite ()*	Magnesiochromite ()*
Magnesite ()*

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
Antigorite ()*	Serpentine Clay	Mg₃Si₂O₅(OH)₄	167	167	0		708
Aragonite ()*	Aragonite	Ca(CO₃)	167	167	1	180830	3250
Chromite ()*	Spinel	Fe²⁺Cr₂O₄	167	167	1	180830	3902
Enstatite ()*	Pyroxene	Mg₂Si₂O₆	167	167	0		944
Magnesiochromite ()*	Spinel	MgCr₂O₄	167	167	0		311
Magnesite ()*	Calcite	Mg(CO₃)	167	167	0		1487

2 Ages assigned to this locality:

	Excel ID	Max Age (Ma)	Min Age (Ma)	Age as listed in reference	Dating Method	Age Interpret	Prioritized?	Sample Source	Sample Num	Run Num	Age from other Locality	Dated Mineral	Minerals explicitely stated as having this age	Age applies to these Elements	MinDat Locality ID	Dated Locality (Max Age)	Location as listed in reference	Reference	Reference DOI	Reference ID	Age Notes
	podchrome-00302	167	167	Middle Jurassic (167.86+0.32-0.40 Ma, CA-TIMS, zircon in plagiogranite)										Cr	95991	Grau Mine (Gruu Mine), North Elder Creek Group (Joyce Mine; Hill Mine; Noble Electric Steel Company Mine; SW Hill Mine; Elder Creek Mine), Tehama Co., California, USA	Grau	Moiser et al. (2012)		USGSSIR2012_5157
	podchrome-00303	167	167	Middle Jurassic (167.86+0.32-0.40 Ma, CA-TIMS, zircon in plagiogranite)										Cr	96049	West Pit (Grau Pit), Grau Mine (Gruu Mine), North Elder Creek Group (Joyce Mine; Hill Mine; Noble Electric Steel Company Mine; SW Hill Mine; Elder Creek Mine), Tehama Co., California, USA	Grau West Pit	Moiser et al. (2012)		USGSSIR2012_5157

Sample	Source Locality	Reference URL

All locality data graciously provided by mindat.org

All age data...