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:
Middletown, East Mayacmas District, Mayacmas Mts (Mayacamas Mts), Lake Co., California, USA

Oldest recorded age at locality: 172
Youngest recorded age at locality: 0

mindat Locality ID: 80849
mindat URL: http://www.mindat.org/loc-80849.html

Tectonic Settings:

Total number of sublocalities beneath "Middletown, East Mayacmas District, Mayacmas Mts (Mayacamas Mts), Lake Co., California, USA": 33
Total number of bottom-level sublocalities: 30

Number of Child Localities: 29
Child Localities:
Black Ranch
Bullion Mine
Copper Prince Mine
Downey Estate Prospect
Dry Creek
Dunkin Lode Mine
East Of Middletown
Great Western-Mirabel Group
Harp And Sons Ranch Deposits
Holmstatt Deposit (Holmstedt Deposit)
Hughes-Bradbury Mine
Joyce Mine
Juanita Occurrence
Kangaroo Court Mine
Langtry Ranch
Maypole Occurrence
Midway Mine (Wilkinson Brothers Mine)
Mirabel Mine (Standard Mine; Bradford Shaft; Great Eastern Shaft)
North Of Middletown
Northeast Of Middletown
Otto-Bullion Mine (Otto Mine)
Placer Realty Corporation Property
Roadcut On Highway To Lower Lake
Smythe Manganese Prospect
South Of Middletown
Sutro Mine
Unknown Hg Mine (5)
Von Glahn Prospects (Henry Von Claim)
VSTO-Bullion Mine

Latitude: 38°43'15"N
Longitude: 122°38'3"W
Decimal Degree (lat, lon): 38.720833333333,-122.63416666667

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.

Amorphous	Calcite	Chalcopyrite	Clay	Feldspar	Malachite	Millerite	None	Not in a structural group	Pectolite
Pyrite	Quartz	Serpentine	Sphalerite	Spinel	Wollastonite

Anorthite ()*	Azurite ()*	Calcite ()*	Chalcocite ()*	Chalcopyrite ()*
Chromite ()*	Chrysotile ()*	Cinnabar ()*	Dolomite ()*	Idrialite ()*
Jamesonite ()*	Malachite ()*	Mercury ()*	Metacinnabar ()*	Millerite ()*
Opal ()*	Pectolite ()*	Pyrite ()*	Quartz ()*	Tiemannite ()*
Wollastonite ()*

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 C Ca Cr Cu Fe H Hg Mg Na Ni O Pb S Sb Se Si

Elements from minerals reported directly at this locality:

Structural Groups for minerals in this locality:
Amorphous Calcite Chalcopyrite Clay Feldspar Malachite Millerite None Not in a structural group Pectolite
Pyrite Quartz Serpentine Sphalerite Spinel Wollastonite

21 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
Anorthite ()*	Feldspar	Ca(Al₂Si₂O₈)	2.9	0	1	160732	1036
Azurite ()*	Not in a structural group	Cu₃(CO₃)₂(OH)₂	2.9	0	1	160711	5509
Calcite ()*	Calcite	Ca(CO₃)	164	0	2	160720,160735	27770
Chalcocite ()*	None	Cu₂S	2.9	0	1	160727	5707
Chalcopyrite ()*	Chalcopyrite	CuFeS₂	2.9	0	1	160737	27198
Chromite ()*	Spinel	Fe²⁺Cr₂O₄	172	164	6	160718,160720,160721,160722,160726,160738	3902
Chrysotile ()*	Serpentine Clay	Mg₃Si₂O₅(OH)₄	2.9	0	1	160731	951
Cinnabar ()*	None	HgS	164	0	7	160710,160720,160723,160724,160729,160730,160733	2600
Dolomite ()*	None	CaMg(CO₃)₂	164	0	2	160720,160730	9895
Idrialite ()*	None	C₂₂H₁₄	164	0	2	160720,160730	15
Jamesonite ()*	None	Pb₄FeSb₆S₁₄	164	164	1	160720	784
Malachite ()*	Malachite	Cu₂(CO₃)(OH)₂	2.9	0	2	160711,160727	12537
Mercury ()*	None	Hg	164	0	2	160720,160730	397
Metacinnabar ()*	Sphalerite	HgS	164	0	2	160720,160730	255
Millerite ()*	Millerite	NiS	164	164	1	160720	1066
Opal ()*	Amorphous	SiO₂·nH₂O	164	164	1	160720	2994
Pectolite ()*	Pectolite	NaCa₂Si₃O₈(OH)	2.9	0	1	160735	363
Pyrite ()*	Pyrite	FeS₂	164	164	1	160720	39462
Quartz ()*	Quartz	SiO₂	164	164	1	160720	61156
Tiemannite ()*	Sphalerite	HgSe	164	164	1	160720	83
Wollastonite ()*	Wollastonite	CaSiO₃	2.9	0	1	160715	1247

6 Ages assigned to this locality:

Excel ID	Max Age (Ma)	Min Age (Ma)	Age as listed in reference	Dating Method	Sample Source	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
Hg-00110	2.9	0		?-?		Yes		Cinnabar, Mercury, Metacinnabar, Schuetteite, Tiemannite	Hg	80795	East Mayacmas District, Mayacmas Mts (Mayacamas Mts), Lake Co., California, USA		Smith et al. (2008)	10.1016/j.epsl.2008.02.029	EPSL269_399
podchrome-00323	164	164	Middle Jurassic (161-168 Ma)						Cr	80774	Great Western Mine (Laguna Western; Black Bart Mine; Tucker Lease), Great Western-Mirabel Group, Middletown, East Mayacmas District, Mayacmas Mts (Mayacamas Mts), Lake Co., California, USA	Black Bart	Moiser et al. (2012)		USGSSIR2012_5157
podchrome-00326	172	166	Middle Jurassic (169±3 U-Pb, zircon in plagiogranite)		zircon		Zircon		Cr	80820	Harp And Sons Ranch Deposits, Middletown, East Mayacmas District, Mayacmas Mts (Mayacamas Mts), Lake Co., California, USA	Harp and Sons Ranch	Moiser et al. (2012)		USGSSIR2012_5157
podchrome-00327	164	164	Middle Jurassic (161-168 Ma)						Cr	80827	Holmstatt Deposit (Holmstedt Deposit), Middletown, East Mayacmas District, Mayacmas Mts (Mayacamas Mts), Lake Co., California, USA	Holmstedt	Moiser et al. (2012)		USGSSIR2012_5157
podchrome-00074	164	164	Middle Jurassic (161-168 Ma)						Cr	80834	Kangaroo Court Mine, Middletown, East Mayacmas District, Mayacmas Mts (Mayacamas Mts), Lake Co., California, USA	Kangaroo Court	Moiser et al. (2012)		USGSSIR2012_5157
podchrome-00274	164	164	Middle Jurassic (161-168 Ma)						Cr	80893	Sutro Mine, Middletown, East Mayacmas District, Mayacmas Mts (Mayacamas Mts), Lake Co., California, USA	Sutro	Moiser et al. (2012)		USGSSIR2012_5157

Sample	Source Locality	Reference URL

All locality data graciously provided by mindat.org

All age data...