Stewart Mine

Prospect in Chaffee county in Colorado, United States with commodities Gold, Silver, Lead, Zinc

Geologic information

Identification information

Deposit ID 10214779
MAS/MILS ID 0080150266
Record type Site
Current site name Stewart Mine
Alternate or previous names Crystal Victoria Mine, Nancy Cleo Mine

Geographic coordinates

Point of reference Town
Geographic coordinates: -106.57812, 39.04221 (WGS84)
Elevation 2164
Location accuracy 100(meters)
(click for info)

Geographic areas

Country State County
United States Colorado Chaffee

Comments on the location information

  • Mine is 1 mile east of Grizzly Peak on the north side of McNasser Gulch, and about 17 miles west of Granite, in the NW/4 sec. 5, T 12 S, R 82 W.


Commodity Importance
Gold Primary
Silver Secondary
Lead Secondary
Zinc Secondary

Materials information

Materials Type of material
Altaite Ore
Arsenopyrite Ore
Chalcopyrite Ore
Galena Ore
Gold Ore
Pyrite Ore
Pyrrhotite Ore
Sphalerite Ore
Calcite Gangue
Quartz Gangue


  • (Local) widespread pyritization and silicification

Mineral occurrence model information

Model code 106
USGS model code 25b
Deposit model name Epithermal vein, Creede
Mark3 model number 58

Host and associated rocks

  • Host or associated Host
    Rock type Plutonic Rock > Granitoid > Granodiorite
    Stratigraphic age (youngest) Proterozoic
  • Host or associated Host
    Rock type Volcanic Rock (Aphanitic)
    Stratigraphic age (youngest) Oligocene

Nearby scientific data

Town (1) -106.57812, 39.04221

Geologic structures

Type of structure Local
Structure description block faults around collapse structure (caldera)

Comments on the geologic information

  • NE-trending quartz-sulfide veins cut the granodiorite and volcanic rocks. Gold occurs in spotty high-grade pockets along the veins and shear zones.

Economic information

Economic information about the deposit and operations

Operation type Underground
Development status Prospect
Commodity type Metallic
Significant No

Mining district

District name Red Mountain District

Land status

Ownership category Unknown

Comments on the production information

  • A small amount of high-grade gold ore has been produced during exploration and development work.

Comments on development

  • Adit, pits, and trenches have been made to explore mineralized structures.

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
U.S. Bureau of Mines Minerals Availability System MAS 0080150266

Bibliographic references

  • Deposit

    COLO BOM 1969

  • Deposit

    Baskin, G. D., 1987, Mineral resources of the Collegiate Peaks Wilderness, Chaffee, Gunnison, Lake, and Pitkin Counties, Colorado: U.S. Bureau of Mines Open File Report MLA 45-87, 100 p.

  • Deposit

    Sunshine Mining Co. Colorado exploration files, unpublished data, Colorado Geological Survey.

Reporter information

Type Date Name Affiliation Comment
Reporter 17-NOV-83 Intermountain Field Operations Center (IFOC) U.S. Bureau of Mines
Updater 15-MAR-06 Beach, Richard A. Colorado Geological Survey