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Sagamore Mangan No. 2 pit, Riverton, Cuyuna North Range, Crow Wing County, Minnesota, USAi
| Regional Level Types | |
|---|---|
| Sagamore Mangan No. 2 pit | Pit (Flooded) |
| Riverton | City |
| Cuyuna North Range | Mountain Range |
| Crow Wing County | County |
| Minnesota | State |
| USA | Country |
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Latitude & Longitude (WGS84):
46° 27' 12'' North , 94° 3' 2'' West
Latitude & Longitude (decimal):
Type:
Pit (Flooded) - last checked 2023
Deposit first discovered:
1911
Köppen climate type:
Nearest Settlements:
| Place | Population | Distance |
|---|---|---|
| Riverton | 116 (2017) | 0.7km |
| Ironton | 561 (2017) | 6.2km |
| Trommald | 101 (2017) | 6.2km |
| Crosby | 2,345 (2017) | 7.8km |
| Merrifield | 140 (2017) | 9.4km |
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 |
|---|---|---|
| Cuyuna Rock, Gem and Mineral Society | Brainerd, Minnesota | 16km |
The Sagamore Mine (Sec 19 T46N R29W) was an enormous open pit mine in the Proteorozic Trommald Formation banded iron formation. The ore was especially rich in manganese, as well as iron. Exploration of the site began in 1911, with strip mining begun in 1919. Over the mine's lifetime it produced more than 10 million tons of ore. Ore was dried in large on-site rotary kilns. The mine is now (2023) a filled lake, and anchors one of the units of the Cuyuna Country State Recreation Area. Allowed activites now include mountain biking up and down the dumps and fishing the well-stocked former pit. Rock collecting is not an allowed activity.
The deposit developed in a large faulted syncline involving thin-bedded facies of the Trommald Formation. The ore was especially manganiferous near the center of the formation. The mine is the co-type locality for groutite. Also notable were tourmaline-rich argillite layers and stilpnomelane-rich veins. Stripping of the glacial overburden exposed interesting Pleistocene fossils and a 1,884 pound mass of float copper.
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
4 valid minerals. 1 (TL) - type locality of valid minerals.
Detailed Mineral List:
| ⓘ Goethite Formula: Fe3+O(OH) References: |
| ⓘ Groutite (TL) Formula: Mn3+O(OH) Type Locality: References: |
| ⓘ Magnetite Formula: Fe2+Fe3+2O4 References: |
| ⓘ Pyrite Formula: FeS2 References: |
Gallery:
List of minerals arranged by Strunz 10th Edition classification
| Group 2 - Sulphides and Sulfosalts | |||
|---|---|---|---|
| ⓘ | Pyrite | 2.EB.05a | FeS2 |
| Group 4 - Oxides and Hydroxides | |||
| ⓘ | Goethite | 4.00. | Fe3+O(OH) |
| ⓘ | Magnetite | 4.BB.05 | Fe2+Fe3+2O4 |
| ⓘ | Groutite (TL) | 4.FD.10 | Mn3+O(OH) |
List of minerals for each chemical element
| H | Hydrogen | |
|---|---|---|
| H | ⓘ Goethite | Fe3+O(OH) |
| H | ⓘ Groutite | Mn3+O(OH) |
| O | Oxygen | |
| O | ⓘ Goethite | Fe3+O(OH) |
| O | ⓘ Groutite | Mn3+O(OH) |
| O | ⓘ Magnetite | Fe2+Fe23+O4 |
| S | Sulfur | |
| S | ⓘ Pyrite | FeS2 |
| Mn | Manganese | |
| Mn | ⓘ Groutite | Mn3+O(OH) |
| Fe | Iron | |
| Fe | ⓘ Goethite | Fe3+O(OH) |
| Fe | ⓘ Magnetite | Fe2+Fe23+O4 |
| Fe | ⓘ Pyrite | FeS2 |
Other Regions, Features and Areas containing this locality
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Sagamore Mangan No. 2 pit, Riverton, Cuyuna North Range, Crow Wing County, Minnesota, USA