Great Western Mine (Laguna Western; Black Bart Mine; Tucker lease), Great Western-Mirabel group, Middletown, East Mayacmas Mining District, Lake County, California, USAi
| Regional Level Types | |
|---|---|
| Great Western Mine (Laguna Western; Black Bart Mine; Tucker lease) | Mine |
| Great Western-Mirabel group | - not defined - |
| Middletown | - not defined - |
| East Mayacmas Mining District | Mining District |
| Lake County | County |
| California | State |
| USA | Country |
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Latitude & Longitude (WGS84):
38° 42' 48'' North , 122° 38' 33'' West
Latitude & Longitude (decimal):
Type:
Köppen climate type:
Nearest Settlements:
| Place | Population | Distance |
|---|---|---|
| Middletown | 1,323 (2011) | 5.0km |
| Hidden Valley Lake | 5,579 (2011) | 12.8km |
| Cobb | 1,778 (2011) | 14.0km |
| Calistoga | 5,330 (2017) | 15.9km |
| Lower Lake | 1,294 (2011) | 22.1km |
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
Local clubs are the best way to get access to collecting localities
| Club | Location | Distance |
|---|---|---|
| Santa Rosa Mineral And Gem Society, Inc. | Santa Rosa, California | 31km |
A former Hg-Cr mine located in sec. 16, T10N, R7W, MDM, 5.0 km (3.1 miles) SSW of Middletown in the Mt. St. Helena area. Alternate coordinates provided: 38°41'31"N, 122°37'51"W.
Mineralization is hosted in rocks of the Alaveras Formation, Franciscan Complex (Serpentinite, chert). The mineralized zone lies along a fault contact between serpentine and Franciscan sedimentary rocks. Ore occurs as veinlets and crystals disseminated in silica-carbonate rock.
Local structure include lithologic contacts; Mayacmas Anticline trending NW.
Related tectonic structures include the Franciscan Melange.
Production data are found in: U.S. Bureau of Mines file data.
Mineralization is hosted in rocks of the Alaveras Formation, Franciscan Complex (Serpentinite, chert). The mineralized zone lies along a fault contact between serpentine and Franciscan sedimentary rocks. Ore occurs as veinlets and crystals disseminated in silica-carbonate rock.
Local structure include lithologic contacts; Mayacmas Anticline trending NW.
Related tectonic structures include the Franciscan Melange.
Production data are found in: U.S. Bureau of Mines file data.
Select Mineral List Type
Standard Detailed Gallery Strunz Chemical ElementsMineral List
13 valid minerals.
Rock Types Recorded
Select Rock List Type
Alphabetical List Tree DiagramDetailed Mineral List:
| ⓘ Calcite Formula: CaCO3 |
| ⓘ Chromite Formula: Fe2+Cr3+2O4 |
| ⓘ Cinnabar Formula: HgS |
| ⓘ Dolomite Formula: CaMg(CO3)2 |
| ⓘ Idrialite Formula: C22H14 |
| ⓘ Jamesonite Formula: Pb4FeSb6S14 Description: A minor mineral here. |
| ⓘ Metacinnabar Formula: HgS |
| ⓘ Millerite Formula: NiS Description: Occurs in very small amounts. References: |
| ⓘ Native Mercury Formula: Hg References: |
| ⓘ Opal Formula: SiO2 · nH2O |
| ⓘ Pyrite Formula: FeS2 |
| ⓘ Quartz Formula: SiO2 |
| ⓘ 'Serpentine Subgroup' Formula: D3[Si2O5](OH)4 |
| ⓘ Tiemannite Formula: HgSe |
List of minerals arranged by Strunz 10th Edition classification
| Group 1 - Elements | |||
|---|---|---|---|
| ⓘ | Native Mercury | 1.AD.05 | Hg |
| Group 2 - Sulphides and Sulfosalts | |||
| ⓘ | Metacinnabar | 2.CB.05a | HgS |
| ⓘ | Tiemannite | 2.CB.05a | HgSe |
| ⓘ | Millerite | 2.CC.20 | NiS |
| ⓘ | Cinnabar | 2.CD.15a | HgS |
| ⓘ | Pyrite | 2.EB.05a | FeS2 |
| ⓘ | Jamesonite | 2.HB.15 | Pb4FeSb6S14 |
| Group 4 - Oxides and Hydroxides | |||
| ⓘ | Chromite | 4.BB.05 | Fe2+Cr3+2O4 |
| ⓘ | Quartz | 4.DA.05 | SiO2 |
| ⓘ | Opal | 4.DA.10 | SiO2 · nH2O |
| Group 5 - Nitrates and Carbonates | |||
| ⓘ | Calcite | 5.AB.05 | CaCO3 |
| ⓘ | Dolomite | 5.AB.10 | CaMg(CO3)2 |
| Group 10 - Organic Compounds | |||
| ⓘ | Idrialite | 10.BA.20 | C22H14 |
| Unclassified | |||
| ⓘ | 'Serpentine Subgroup' | - | D3[Si2O5](OH)4 |
List of minerals for each chemical element
| H | Hydrogen | |
|---|---|---|
| H | ⓘ Idrialite | C22H14 |
| H | ⓘ Opal | SiO2 · nH2O |
| H | ⓘ Serpentine Subgroup | D3[Si2O5](OH)4 |
| C | Carbon | |
| C | ⓘ Calcite | CaCO3 |
| C | ⓘ Dolomite | CaMg(CO3)2 |
| C | ⓘ Idrialite | C22H14 |
| O | Oxygen | |
| O | ⓘ Calcite | CaCO3 |
| O | ⓘ Chromite | Fe2+Cr23+O4 |
| O | ⓘ Dolomite | CaMg(CO3)2 |
| O | ⓘ Opal | SiO2 · nH2O |
| O | ⓘ Quartz | SiO2 |
| O | ⓘ Serpentine Subgroup | D3[Si2O5](OH)4 |
| Mg | Magnesium | |
| Mg | ⓘ Dolomite | CaMg(CO3)2 |
| Si | Silicon | |
| Si | ⓘ Opal | SiO2 · nH2O |
| Si | ⓘ Quartz | SiO2 |
| Si | ⓘ Serpentine Subgroup | D3[Si2O5](OH)4 |
| S | Sulfur | |
| S | ⓘ Cinnabar | HgS |
| S | ⓘ Jamesonite | Pb4FeSb6S14 |
| S | ⓘ Metacinnabar | HgS |
| S | ⓘ Millerite | NiS |
| S | ⓘ Pyrite | FeS2 |
| Ca | Calcium | |
| Ca | ⓘ Calcite | CaCO3 |
| Ca | ⓘ Dolomite | CaMg(CO3)2 |
| Cr | Chromium | |
| Cr | ⓘ Chromite | Fe2+Cr23+O4 |
| Fe | Iron | |
| Fe | ⓘ Chromite | Fe2+Cr23+O4 |
| Fe | ⓘ Jamesonite | Pb4FeSb6S14 |
| Fe | ⓘ Pyrite | FeS2 |
| Ni | Nickel | |
| Ni | ⓘ Millerite | NiS |
| Se | Selenium | |
| Se | ⓘ Tiemannite | HgSe |
| Sb | Antimony | |
| Sb | ⓘ Jamesonite | Pb4FeSb6S14 |
| Hg | Mercury | |
| Hg | ⓘ Cinnabar | HgS |
| Hg | ⓘ Native Mercury | Hg |
| Hg | ⓘ Metacinnabar | HgS |
| Hg | ⓘ Tiemannite | HgSe |
| Pb | Lead | |
| Pb | ⓘ Jamesonite | Pb4FeSb6S14 |
Other Regions, Features and Areas containing this locality
North AmericaContinent
- Coast MountainsMountain Range
North America PlateTectonic Plate
- California Coast RangesAccretionary Complex
- Franciscan DomainDomain
USA
- California
- Mayacamas MountainsMountain Range
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Great Western Mine, Great Western-Mirabel group, Middletown, East Mayacmas Mining District, Lake County, California, USA