Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite
Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
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Middletown, East Mayacmas Mining District, Lake County, California, USAi
Regional Level Types
Middletown- not defined -
East Mayacmas Mining DistrictMining District
Lake CountyCounty
CaliforniaState
USACountry

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PhotosMapsSearchMineralogy
01752680017272093474660.jpg
Idrialite

Great Western Mine, Great Western-Mirabel group, Middletown, East Mayacmas Mining District, Lake County, California, USA
03129960017272093476611.jpg
Cinnabar, etc.

Great Western Mine, Great Western-Mirabel group, Middletown, East Mayacmas Mining District, Lake County, California, USA
04539870017272036011441.jpg
Idrialite

Great Western Mine, Great Western-Mirabel group, Middletown, East Mayacmas Mining District, Lake County, California, USA
01752680017272093474660.jpg
Idrialite

Great Western Mine, Great Western-Mirabel group, Middletown, East Mayacmas Mining District, Lake County, California, USA
07354550017272035938792.jpg
Cinnabar, etc.

Great Western Mine, Great Western-Mirabel group, Middletown, East Mayacmas Mining District, Lake County, California, USA
04539870017272036011441.jpg
Idrialite

Great Western Mine, Great Western-Mirabel group, Middletown, East Mayacmas Mining District, Lake County, California, USA
01752680017272093474660.jpg
Idrialite

Great Western Mine, Great Western-Mirabel group, Middletown, East Mayacmas Mining District, Lake County, California, USA
01182320017272035989769.jpg
Cinnabar, etc.

Great Western Mine, Great Western-Mirabel group, Middletown, East Mayacmas Mining District, Lake County, California, USA
Latitude & Longitude (WGS84):
38° 45' 9'' North , 122° 36' 50'' West
Latitude & Longitude (decimal):
38.75250,-122.61389
GRN:
N26W69
Köppen climate type:
Csb : Warm-summer Mediterranean climate
Nearest Settlements:
PlacePopulationDistance
Middletown1,323 (2011)0.1km
Hidden Valley Lake5,579 (2011)7.8km
Cobb1,778 (2011)12.2km
Lower Lake1,294 (2011)17.6km
Calistoga5,330 (2017)19.5km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Santa Rosa Mineral And Gem Society, Inc.Santa Rosa, California36km
Mindat Locality ID:
80849
Long-form identifier:
mindat:1:2:80849:6
GUID (UUID V4):
0


A Hg mining area.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded from this region.


Mineral List

Mineral list contains entries from the region specified including sub-localities

21 valid minerals.

Rock Types Recorded


Rock list contains entries from the region specified including sub-localities

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Anorthite
Formula: Ca(Al2Si2O8)
Description: Occus as fine cleavage fragments.
ⓘ Azurite
Formula: Cu3(CO3)2(OH)2
ⓘ Calcite
Formula: CaCO3
ⓘ Chalcocite
Formula: Cu2S
ⓘ Chalcopyrite
Formula: CuFeS2
Description: Occurs as high-grade ore.
ⓘ Chromite
Formula: Fe2+Cr3+2O4
Localities: Reported from at least 6 localities in this region.
ⓘ Chrysotile
Formula: Mg3(Si2O5)(OH)4
Description: Occurs in serpentine.
ⓘ Cinnabar
Formula: HgS
Localities: Reported from at least 7 localities in this region.
ⓘ Dolomite
Formula: CaMg(CO3)2
Description: Occurs well-crystallized as gangue in Hg ores.
ⓘ Idrialite
Formula: C22H14
ⓘ Jamesonite
Formula: Pb4FeSb6S14
Description: A minor mineral here.
ⓘ Malachite
Formula: Cu2(CO3)(OH)2
ⓘ Metacinnabar
Formula: HgS
ⓘ Millerite
Formula: NiS
Description: Occurs in very small amounts.
ⓘ Native Mercury
Formula: Hg
ⓘ Opal
Formula: SiO2 · nH2O
ⓘ Pectolite
Formula: NaCa2Si3O8(OH)
Description: Occurs as extensive veins of fibrous material with calcite in serpentine.
ⓘ 'Psilomelane'
ⓘ Pyrite
Formula: FeS2
ⓘ Quartz
Formula: SiO2
ⓘ 'Serpentine Subgroup'
Formula: D3[Si2O5](OH)4
ⓘ Tiemannite
Formula: HgSe
ⓘ Wollastonite
Formula: Ca3(Si3O9)
Colour: White
Description: Material is drusy.

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Mercury1.AD.05Hg
Group 2 - Sulphides and Sulfosalts
ⓘChalcocite2.BA.05Cu2S
ⓘMetacinnabar2.CB.05aHgS
ⓘTiemannite2.CB.05aHgSe
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘMillerite2.CC.20NiS
ⓘCinnabar2.CD.15aHgS
ⓘPyrite2.EB.05aFeS2
ⓘJamesonite2.HB.15Pb4FeSb6S14
Group 4 - Oxides and Hydroxides
ⓘChromite4.BB.05Fe2+Cr3+2O4
ⓘQuartz4.DA.05SiO2
ⓘOpal4.DA.10SiO2 · nH2O
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘDolomite5.AB.10CaMg(CO3)2
ⓘAzurite5.BA.05Cu3(CO3)2(OH)2
ⓘMalachite5.BA.10Cu2(CO3)(OH)2
Group 9 - Silicates
ⓘChrysotile9.00.Mg3(Si2O5)(OH)4
ⓘPectolite9.DG.05NaCa2Si3O8(OH)
ⓘWollastonite9.DG.05Ca3(Si3O9)
ⓘAnorthite9.FA.35Ca(Al2Si2O8)
Group 10 - Organic Compounds
ⓘIdrialite10.BA.20C22H14
Unclassified
ⓘ'Psilomelane'-
ⓘ'Serpentine Subgroup'-D3[Si2O5](OH)4

List of minerals for each chemical element

HHydrogen
Hⓘ AzuriteCu3(CO3)2(OH)2
Hⓘ ChrysotileMg3(Si2O5)(OH)4
Hⓘ IdrialiteC22H14
Hⓘ MalachiteCu2(CO3)(OH)2
Hⓘ OpalSiO2 · nH2O
Hⓘ PectoliteNaCa2Si3O8(OH)
Hⓘ Serpentine SubgroupD3[Si2O5](OH)4
CCarbon
Cⓘ AzuriteCu3(CO3)2(OH)2
Cⓘ CalciteCaCO3
Cⓘ DolomiteCaMg(CO3)2
Cⓘ IdrialiteC22H14
Cⓘ MalachiteCu2(CO3)(OH)2
OOxygen
Oⓘ AnorthiteCa(Al2Si2O8)
Oⓘ AzuriteCu3(CO3)2(OH)2
Oⓘ CalciteCaCO3
Oⓘ ChrysotileMg3(Si2O5)(OH)4
Oⓘ ChromiteFe2+Cr23+O4
Oⓘ DolomiteCaMg(CO3)2
Oⓘ MalachiteCu2(CO3)(OH)2
Oⓘ OpalSiO2 · nH2O
Oⓘ PectoliteNaCa2Si3O8(OH)
Oⓘ QuartzSiO2
Oⓘ WollastoniteCa3(Si3O9)
Oⓘ Serpentine SubgroupD3[Si2O5](OH)4
NaSodium
Naⓘ PectoliteNaCa2Si3O8(OH)
MgMagnesium
Mgⓘ ChrysotileMg3(Si2O5)(OH)4
Mgⓘ DolomiteCaMg(CO3)2
AlAluminium
Alⓘ AnorthiteCa(Al2Si2O8)
SiSilicon
Siⓘ AnorthiteCa(Al2Si2O8)
Siⓘ ChrysotileMg3(Si2O5)(OH)4
Siⓘ OpalSiO2 · nH2O
Siⓘ PectoliteNaCa2Si3O8(OH)
Siⓘ QuartzSiO2
Siⓘ WollastoniteCa3(Si3O9)
Siⓘ Serpentine SubgroupD3[Si2O5](OH)4
SSulfur
Sⓘ ChalcopyriteCuFeS2
Sⓘ ChalcociteCu2S
Sⓘ CinnabarHgS
Sⓘ JamesonitePb4FeSb6S14
Sⓘ MetacinnabarHgS
Sⓘ MilleriteNiS
Sⓘ PyriteFeS2
CaCalcium
Caⓘ AnorthiteCa(Al2Si2O8)
Caⓘ CalciteCaCO3
Caⓘ DolomiteCaMg(CO3)2
Caⓘ PectoliteNaCa2Si3O8(OH)
Caⓘ WollastoniteCa3(Si3O9)
CrChromium
Crⓘ ChromiteFe2+Cr23+O4
FeIron
Feⓘ ChalcopyriteCuFeS2
Feⓘ ChromiteFe2+Cr23+O4
Feⓘ JamesonitePb4FeSb6S14
Feⓘ PyriteFeS2
NiNickel
Niⓘ MilleriteNiS
CuCopper
Cuⓘ AzuriteCu3(CO3)2(OH)2
Cuⓘ ChalcopyriteCuFeS2
Cuⓘ ChalcociteCu2S
Cuⓘ MalachiteCu2(CO3)(OH)2
SeSelenium
Seⓘ TiemanniteHgSe
SbAntimony
Sbⓘ JamesonitePb4FeSb6S14
HgMercury
Hgⓘ CinnabarHgS
Hgⓘ Native MercuryHg
Hgⓘ MetacinnabarHgS
Hgⓘ TiemanniteHgSe
PbLead
Pbⓘ JamesonitePb4FeSb6S14

Localities in this Region

USA
USA

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate
USA

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

Bradley, W.W. (1918), Quicksilver resources of California, with a section on metallurgy and ore dressing: California Mining Bureau. Bulletin 78, 389 pp.
Ransome, Alfred Leslie & J.L. Kellogg (1939), Quicksilver resources of California: California Division Mines Report 35: 353-558.
Holmes, G.H. (1965) Mercury in California. US Bureau of Mines Information Circular 8252: 87-206
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