Vote for your favorite mineral in #MinCup26! - Quartz vs. Asagiite
It's a classic vs a newbie as the most common named mineral in the crust Quartz is up against an exceedingly-rare sea foam-green mineral discovered just a few years ago Asagiite.
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Mahnomen No. 4 mine, Ironton, Cuyuna North Range, Crow Wing County, Minnesota, USAi
Regional Level Types
Mahnomen No. 4 mineMine
IrontonCity
Cuyuna North RangeMountain Range
Crow Wing CountyCounty
MinnesotaState
USACountry

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Latitude & Longitude (WGS84):
46° 29' 12'' North , 93° 59' 21'' West
Latitude & Longitude (decimal):
46.48685,-93.98925
GeoHash:
G#: cbm0mnxje
GRN:
N31W48
Type:
Mine
Köppen climate type:
Dfb : Warm-summer humid continental climate
Nearest Settlements:
PlacePopulationDistance
Ironton561 (2017)1.4km
Crosby2,345 (2017)2.5km
Trommald101 (2017)3.0km
Riverton116 (2017)5.7km
Cuyuna346 (2017)6.1km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Cuyuna Rock, Gem and Mineral SocietyBrainerd, Minnesota22km
Mindat Locality ID:
52920
Long-form identifier:
mindat:1:2:52920:7
GUID (UUID V4):
0


The Mahnomen #4 Mine (Sec 10 T46N R29W) was an open pit mine, part of the interconnected Mahnomen Mine group. The ore was in a large syncline exposing the Proterozoic Trommald Banded Iron Formation. The mines is also the type locality for the underlying Mahnomen Formation, which consists mostly of quartzite and slate. The flooded pit and overgrown dumps of the mine site are now a major part of the Cuyuna Country State Recreation area. It is administered by the Minnesota Department of Natural Resources, and no collecting is permitted.Sec 3 T46N R29W

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


1 valid mineral.

Detailed Mineral List:

ⓘ Magnetite
Formula: Fe2+Fe3+2O4

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4

List of minerals for each chemical element

OOxygen
Oⓘ MagnetiteFe2+Fe23+O4
FeIron
Feⓘ MagnetiteFe2+Fe23+O4

Other Databases

Link to USGS MRDS:10170345

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate

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

Harder, E. C., Johnston, A. W. (1918) Preliminary Report on the Geology of East Central Minnesota Including the Cuyuna Iron-ore District. Bulletin 15. Minnesota Geological Survey
Schmidt, R.G. (1963) Geology and ore deposits of the Cuyuna North Range, Minnesota: U.S. Geological Survey Professional Paper 407, 96 p.
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