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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Marcasite from
Fox Hills Formation, Windsor Reservoir, Larimer County, Colorado, USA


Locality type:Formation
Classification
Species:Marcasite
Formula:FeS2
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Marcasite data
Locality Data:Click here to view Fox Hills Formation, Windsor Reservoir, Larimer County, Colorado, USA
Data Identifiers
Mindat Occurrence Record ID:488746
Long-form Identifier:1:3:488746:1
GUID (UUID V4):0
Nearest other occurrences of Marcasite
36.9km (22.9 miles) ⓘTreasure Hill Mine (Unpatented Claims: Treasure Hill 1-6), Livermore Area, Larimer County, Colorado, USA
43.4km (27.0 miles) ⓘRound Butte, Niobrara Formation, Larimer County, Colorado, USA
62.0km (38.5 miles) ⓘCopper King Mine (Claims: Black Hawk No. 1; Black Hawk No. 2), Prairie Divide Mining District (St. Cloud Mining District), Larimer County, Colorado, USA
67.3km (41.8 miles) ⓘOsceola, Gold Hill Mining District, Boulder County, Colorado, USA
67.6km (42.0 miles) ⓘInterocean Mine, Gold Hill Mining District, Boulder County, Colorado, USA
67.6km (42.0 miles) ⓘRichard occurrence (Minnie Bell; Washburn; White Eagle; Dolly; Plough Boy; Oceola; Gillaspie), Gold Hill Mining District, Boulder County, Colorado, USA
67.7km (42.1 miles) ⓘArcher, Gold Hill Mining District, Boulder County, Colorado, USA
71.1km (44.2 miles) ⓘLogan & Sunbeam Occurrence, Gold Hill Mining District, Boulder County, Colorado, USA
71.1km (44.2 miles) ⓘGrand Republic Occurrence, Gold Hill Mining District, Boulder County, Colorado, USA
71.7km (44.5 miles) ⓘNancy Wood mine (Sugar Loaf; Forest; Pittsburg; Gray Copper), Gold Hill, Gold Hill Mining District, Boulder County, Colorado, USA
References
Eckel, Edwin Butt; Cobban, Robert R.; Mosburg, Shirley K.; Foord, Eugene E. (1997) Minerals of Colorado. Fulcrum Publishing.
 
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