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Actinolite from
Cotopaxi Mine (Cotopaxi lode; Gumaer Mine; Fannie lode; Fannie Mill), Mine Gulch, Cotopaxi, Cotopaxi Mining District, Fremont County, Colorado, USA


Locality type:Mine
Classification
Species:Actinolite
Formula:◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Actinolite data
Locality Data:Click here to view Cotopaxi Mine (Cotopaxi lode; Gumaer Mine; Fannie lode; Fannie Mill), Mine Gulch, Cotopaxi, Cotopaxi Mining District, Fremont County, Colorado, USA
Data Identifiers
Mindat Occurrence Record ID:355199
Long-form Identifier:1:3:355199:8
GUID (UUID V4):0
Nearest other occurrences of Actinolite
18.3km (11.4 miles) ⓘVermiculite Mine (MRDS - 10013422), Gem Park complex, Fremont County, Colorado, USA
32.0km (19.9 miles) ⓘMidway Spring, Chaffee County, Colorado, USA
32.3km (20.1 miles) ⓘHorseshoe Mine (School Section Deposit), Grape Creek Mining District (Greenhorn Mining District), Fremont County, Colorado, USA
32.9km (20.5 miles) ⓘJoker Mine (Rocky Mountain Boy Claims Patented Claims), Grape Creek Mining District (Greenhorn Mining District), Fremont County, Colorado, USA
33.0km (20.5 miles) ⓘIsabel Mine, Guffey Mining District (Freshwater Mining District), Fremont County, Colorado, USA
35.4km (22.0 miles) ⓘHomestake Mine, Turret Mining District, Chaffee County, Colorado, USA
35.5km (22.1 miles) ⓘBumback Gulch, Twin Mountain, Eight Mile Park Pegmatite Mining District, Fremont County, Colorado, USA
35.9km (22.3 miles) ⓘCalumet Mine, Turret Mining District, Chaffee County, Colorado, USA
38.1km (23.7 miles) ⓘSedalia Mine (Sedalia Copper Mine), Sedalia Mining District, Chaffee County, Colorado, USA
38.3km (23.8 miles) ⓘMill Gulch Mine, Guffey Mining District, Park County, Colorado, USA
References
Am Min 50:1179-1212
(2005) Mineral Resources Data System (MRDS), US Geological Survey.
Spry, Paul G.; McFadden, Scott; Teale, Graham S.; Alers, Brian; Shallow, John M.; Glenn, Justin M. (2022) Nodular sillimanite rocks as field indicators to metamorphosed massive sulfide deposits. Ore Geology Reviews, 141. 104632 doi:10.1016/j.oregeorev.2021.104632
 
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