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Old Mass Mine, Mass City, Ontonagon County, Michigan, USAi
| Regional Level Types | |
|---|---|
| Old Mass Mine | Mine |
| Mass City | Unincorporated Community |
| Ontonagon County | County |
| Michigan | State |
| USA | Country |
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Latitude & Longitude (WGS84):
46° 45' 26'' North , 89° 6' 47'' West
Latitude & Longitude (decimal):
Type:
Köppen climate type:
Nearest Settlements:
| Place | Population | Distance |
|---|---|---|
| Ontonagon | 1,324 (2017) | 19.8km |
| White Pine | 474 (2017) | 35.9km |
| South Range | 746 (2017) | 49.8km |
| Watersmeet | 428 (2017) | 54.6km |
Commodities (Major) - Copper
Deposit Type: Secondary Enrichment
Development Status: Past Producer
Deposit Model: 96: Native Cu
Host Rock Unit: Portage Lake Volcanics
Host Rock: Basalt
The Old Mass Mine was organized in 1856 to work the property formerly known as the Johnson Pre-Emption or Johnson Tract. The mine worked one shaft that was sunk when it was the Johnson Tract. Between 1856 and 1860, six shallow shafts were sunk. Work was suspended in 1860 and resumed in 1864 when work focused on the Evergreen Lode. Work was again stopped in 1868 and the mine was worked on tribute until 1874. The company resumed mining in 1875 until it again closed the mine in 1884. The mine was worked on tribute until 1889 when the mine became part of the Mass Consolidated Mining Company. Between 1856 and 1888, the mine produced approximately 4.8 million pounds of copper. Today, the rock piles produce fine specimens of copper, silver, datolite, and several micro minerals.
Select Mineral List Type
Standard Detailed Gallery Strunz Chemical ElementsCommodity List
This is a list of exploitable or exploited mineral commodities recorded at this locality.Mineral List
7 valid minerals.
Rock Types Recorded
Note: data is currently VERY limited. Please bear with us while we work towards adding this information!
Select Rock List Type
Alphabetical List Tree DiagramDetailed Mineral List:
| ⓘ Calcite Formula: CaCO3 |
| ⓘ 'Chlorite Group' |
| ⓘ Datolite Formula: CaB(SiO4)(OH) |
| ⓘ Epidote Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| ⓘ 'K Feldspar' |
| ⓘ Native Copper Formula: Cu |
| ⓘ Native Silver Formula: Ag |
| ⓘ Pumpellyite-(Mg) Formula: Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH) |
| ⓘ Quartz Formula: SiO2 |
Gallery:
List of minerals arranged by Strunz 10th Edition classification
| Group 1 - Elements | |||
|---|---|---|---|
| ⓘ | Native Copper | 1.AA.05 | Cu |
| ⓘ | Native Silver | 1.AA.05 | Ag |
| Group 4 - Oxides and Hydroxides | |||
| ⓘ | Quartz | 4.DA.05 | SiO2 |
| Group 5 - Nitrates and Carbonates | |||
| ⓘ | Calcite | 5.AB.05 | CaCO3 |
| Group 9 - Silicates | |||
| ⓘ | Datolite | 9.AJ.20 | CaB(SiO4)(OH) |
| ⓘ | Epidote | 9.BG.05a | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| ⓘ | Pumpellyite-(Mg) | 9.BG.20 | Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH) |
| Unclassified | |||
| ⓘ | 'Chlorite Group' | - | |
| ⓘ | 'K Feldspar' | - | |
List of minerals for each chemical element
| H | Hydrogen | |
|---|---|---|
| H | ⓘ Datolite | CaB(SiO4)(OH) |
| H | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| H | ⓘ Pumpellyite-(Mg) | Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH) |
| B | Boron | |
| B | ⓘ Datolite | CaB(SiO4)(OH) |
| C | Carbon | |
| C | ⓘ Calcite | CaCO3 |
| O | Oxygen | |
| O | ⓘ Calcite | CaCO3 |
| O | ⓘ Datolite | CaB(SiO4)(OH) |
| O | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| O | ⓘ Pumpellyite-(Mg) | Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH) |
| O | ⓘ Quartz | SiO2 |
| Mg | Magnesium | |
| Mg | ⓘ Pumpellyite-(Mg) | Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH) |
| Al | Aluminium | |
| Al | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| Al | ⓘ Pumpellyite-(Mg) | Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH) |
| Si | Silicon | |
| Si | ⓘ Datolite | CaB(SiO4)(OH) |
| Si | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| Si | ⓘ Pumpellyite-(Mg) | Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH) |
| Si | ⓘ Quartz | SiO2 |
| Ca | Calcium | |
| Ca | ⓘ Calcite | CaCO3 |
| Ca | ⓘ Datolite | CaB(SiO4)(OH) |
| Ca | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| Ca | ⓘ Pumpellyite-(Mg) | Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH) |
| Fe | Iron | |
| Fe | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| Cu | Copper | |
| Cu | ⓘ Native Copper | Cu |
| Ag | Silver | |
| Ag | ⓘ Native Silver | Ag |
Other Regions, Features and Areas containing this locality
North AmericaContinent
North America PlateTectonic Plate
- Mid-continent DomainDomain
- Mid-continent RiftNarrow Rift
USA
- Michigan
- Keweenaw PeninsulaPeninsula
- Midcontinent RiftGeologic Province
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Old Mass Mine, Mass City, Ontonagon County, Michigan, USA