1. Mineral Resources
  2. Online Spatial Data
  3. Mineral Resource Data System (MRDS)

Kokomo District

Past Producer in Summit county in Colorado, United States with commodities Zinc, Silver, Lead, Gold, Copper, Molybdenum
Map
XML
JSON
KML
B
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Alteration
  8. Mineral occurrence model information
  9. Host and associated rocks
  10. Nearby scientific data
  11. Geologic structures
  12. Economic information about the deposit and operations
  13. Mining district
  14. Links to other databases
  15. Bibliographic references
  16. Reporter information

Geologic information

Identification information

Deposit ID 10108243
MRDS ID DC03563
Record type District
Current site name Kokomo District
Alternate or previous names Robinson, McNulty
Included sites Tenmile District (or Tenmile Area)

Comments on the site names

  • Kokomo is the preferred name for the district that includes the productive replacement deposits. Tenmile includes the drainage of Tenmile Creek above Dillon, a much broader area.

Geographic coordinates

Geographic coordinates: -106.19089, 39.42499 (WGS84)
Location accuracy 1000(meters)

Site location context

Political divisions (FIPS codes)

Summit(county)

Colorado(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Copper Mountain(quadrangle 1:24,000 scale)

Leadville(quadrangle 1:100,000 scale)

Leadville(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Blue(hydrologic unit)

Colorado Headwaters(hydrologic accounting unit)

Colorado Headwaters(hydrologic subregion)

Upper Colorado(hydrologic region)

Federal lands

White River National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State County
United States Colorado Summit

Comments on the location information

  • The Kokomo district occupies the valley of upper Tenmile Creek and its drainage basin above (south of) Wheeler Junction nearly to its headwaters and the Lake-Summit county line. It adjoins the Climax district on the south, and the upper Blue River district on the east side of the Tenmile Range, and is sometimes included in the larger Tenmile district. Most productive deposits lie within 2 miles of Kokomo (townsite) in sec. 23, T 7 S, R 79 W.
  • Much of the district is now covered by tailings from the Climax mine and mill.

Commodities

Commodity Importance
Zinc Critical Primary
Silver Primary
Lead Primary
Gold Primary
Copper Secondary
Molybdenum Secondary

Comments on the commodity information

  • On the basis of recorded production (1905-1965), and current (Jan. 2006) metal prices, zinc is the dominant metal, but values of silver, lead, and gold are also important. Trace amounts of molybdenite, the dominant ore mineral at the giant Climax deposit just to the south of the district, occur in high-temperature deposits.
  • Gangue contains carbonate minerals.

Materials information

Materials Type of material
Anglesite Ore
Galena Ore
Cerussite Ore
Gold Ore
Covellite Ore
Marcasite Ore
Malachite Ore
Pyrite Ore
Smithsonite Ore
Pyrrhotite Ore
Silver Ore
Sphalerite Ore
Chalcopyrite Ore
Limonite Gangue
Wad Gangue

Alteration

  • (Local) widespread silicification (jasperoid)

Mineral occurrence model information

Model code 72
USGS model code 19a
Deposit model name Polymetallic replacement
Mark3 model number 47

Host and associated rocks

  • Host or associated Host
    Rock type Sedimentary Rock > Carbonate > Limestone
    Rock unit name Robinson, White Quail, and Jacque Mountain Members of the Minturn Formation
    Stratigraphic age (youngest) Proterozoic
  • Host or associated Associated
    Rock type Metamorphic Rock > Metasedimentary Rock
    Rock unit name granulite, banded gneiss, migmatite
    Stratigraphic age (youngest) Proterozoic
  • Host or associated Associated
    Rock type Plutonic Rock > Granitoid
    Rock unit name granitic rocks and pegmatite
    Stratigraphic age (youngest) Pennsylvanian
  • Host or associated Associated
    Rock type Sedimentary Rock > Mixed Clastic/Carbonate Rock
    Rock unit name Minturn Formation
    Stratigraphic age (youngest) Pennsylvanian
  • Host or associated Associated
    Rock type Sedimentary Rock > Clastic Sedimentary Rock
    Rock unit name Maroon Formation
    Stratigraphic age (youngest) Permian
  • Host or associated Associated
    Rock type Plutonic Rock > Granitoid
    Rock unit name various quartz monzonite porphyry stocks, sills, and dikes
    Stratigraphic age (youngest) Tertiary

Nearby scientific data

(1) -106.19089, 39.42499
ListMap

Economic information

Geologic structures

Type of structure Local
Structure description Kokomo syncline, many small high-angle faults

Comments on the ore body information

  • Major ore and gangue minerals in unoxidized replacement deposits (orebody 1) and in oxidized replacement deposits (orebody 2) are listed.

Comments on the geologic information

  • Ore deposit types include placers, oxidized and unoxidized massive sulfide replacement ores (the most productive), veins, and high-temperature metasomatic deposits.

Economic information about the deposit and operations

Operation type Surface-Underground
Development status Past Producer
Significant Yes

Mining district

District name Kokomo District

Comments on the production information

  • McNulty Gulch placers, discovered in 1860, first brought miners into the district, and produced a modest amount of gold and silver.
  • Rich oxidized silver-lead ore was discovered in sedimentary rocks in 1878, resulting in a rush to the district and production increased greatly during the next few years, before the rich ore was mined out. Value of production before 1905 is estimated to be at least $10 million.
  • Records for 1905 to 1965 show that production included 26,860 oz. of gold, 1,792,278 oz. silver. 501,486 lb. copper, 30,423,894 lb. lead, and 74,873,416 lb. zinc, from about 514,000 tons of ore.

Comments on development

  • In 1895 the Wilfley concentrating table was developed and used in the Wilfley mill here to successfully separate mixed sulfide ores of lead and zinc.

Reference information

Bibliographic references

  • Deposit

    SHARPS, 1963: CSM MIN. IND. BULL., VOL. 6, NO. 6

  • Deposit

    CONSV. DIV. COMP. DATE, 8,65

  • Deposit

    BERGENDAHL, M.H., AND KOSCHMANN, A.H., 1971, ORE DEPOSITS OF THE KOKOMO-TENMILE DISTRICT, COLORADO: U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 652, 53 P.

  • Deposit

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

  • Deposit

    Koschmann, A. H., and Wells, F. G., 1946, Preliminary report on the Kokomo mining district, Colorado: Colorado Scientific Society Proceedings, v. 15, no. 2, p. 51-112.

  • Deposit

    Dempsey, S., and Fell, J. E., 1986, Mining the summit-Colorado's Ten Mile district, 1860-1960: Norman, University of Oklahoma Press.

  • Names

    Dunn, L.G, 2003, Colorado mining districts: A reference: Golden, Colo., Colorado School of Mines Library, 364 p.

  • Deposit

    Mach, C. J., 1992, Geology and mineral deposits of the Kokomo district, Colorado: Fort Collins, CO, Colorado State University, M.S. thesis, 154 p.

Reporter information

Type Date Name Affiliation Comment
Reporter 26-JAN-06 Beach, Richard A. Colorado Geological Survey
Editor 16-APR-10 Wilson, Anna B. U.S. Geological Survey deleted duplicate record DC03563 = newMRDS 60000403.

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.

Maps centered on this site

Authoritative Colorado resources

These are landing pages for further research — the state agencies don't currently expose per-mine deep links.