Jim-Montana

Prospect in Alaska, United States with commodities Copper, Zinc, Silver, Lead
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. Economic information about the deposit and operations
  12. Mining district
  13. Links to other databases
  14. Bibliographic references
  15. General comments
  16. Reporter information

Geologic information

Identification information

Deposit ID 10094022
MRDS ID A012143
Record type Site
Current site name Jim-Montana

Geographic coordinates

Geographic coordinates: -148.91335, 67.81973 (WGS84)
Relative position The Jim-Montana property lies in the hills immediately south of the North Fork Chandalar River and approximately 8 miles south-southwest of Reds Lake. The reference point is located near the south-center of the Jim-Montana claim group (secs. 28, 33, T. 35 N., R. 6 W., of the Fairbanks Meridian) and is generally the same as loc. 34 in DeYoung (1978). The claims extend approximately a mile west-northwest and east-southeast from the reference point. The Jim-Montana [and IF(?)] property is west of and contiguous with the Mowgli-Sher Khan claim group (CH094), and together they form one large claim block. The location is accurate within a 1-mile radius.

Site location context

Political divisions (FIPS codes)

Yukon-Koyukuk(Census area)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Chandalar D-4(quadrangle 1:63,360 scale)

Chandalar N(quadrangle 1:100,000 scale)

Chandalar C(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Alaska(hydrologic region)

Federal lands

BLM(Federal land areas administered by BLM)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary
Zinc Critical Primary
Silver Secondary
Lead Secondary

Materials information

Materials Type of material
Chalcopyrite Ore
Galena Ore
Sphalerite Ore
Tennantite Ore

Alteration

  • (Local) Calc-silicate(?).

Mineral occurrence model information

Model code 60
USGS model code 18c
Deposit model name Skarn Zn-Pb
Mark3 model number 22

Host and associated rocks

  • Host or associated Host
    Rock type Sedimentary Rock > Carbonate > Limestone
    Rock unit name Skajit Limestone
    Rock description Skajit Limestone
    Stratigraphic age (youngest) Late Devonian

Nearby scientific data

(1) -148.91335, 67.81973

Economic information

Comments on the geologic information

  • Geologic Description = Early descriptions of this prospect indicated only the presence of disseminated chalcopyrite and sphalerite with minor galena, tennantite, and malachite stains in skarn in the Silurian/Devonian Skajit Limestone (Grybeck, 1977; DeYoung, 1978). Newberry and others (1986) included it in a group of skarn deposits that form a belt northwest of and related to the granitic rocks of the Devonian(?) Horace Mountain plutons. Many of these skarns exhibit both garnet and pyroxene prograde and epidote and actinolite retrograde mineral assemblages, and Newberry and others (1986) stated that the mineralogy, mineralization, and alteration of these skarns categorize them as continental-margin, porphyry-related copper skarns. Newberry and others (1986) classified the prospect, as a Cu-Zn-Pb prospect and Newberry and others (1997) suggest that these Pb-Zn-rich skarns represent distal concentrations surrounding porphyry systems in the Chandalar district. Newberry and others (1997) classify the Jim-Montana deposit as a calcic Zn-Pb skarn and replacement body. The country rock near this prospect is principally Devonian Skajit Limestone (Brosgi and Reiser, 1964).
  • Age = Devonian based on reported Early Devonian Pb/Pb zircon ages from the associated Baby Creek batholith and Horace Mountain plutons (Dillon and others, 1996).

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Chandalar

Comments on the workings information

  • Workings / Exploration = Claims staked in 1972 and 1975.

Reference information

Bibliographic references

Comments on the references

  • Primary Reference = Grybeck, 1977

General comments

Subject category Comment text
Deposit Model Name = Zn-Pb skarn deposits(?) (Cox and Singer, 1986; model 18c)
Deposit Other Comments = See also: Mowgli-Sher Khan prospect (CH094).? Alaska Kardex Nos. 031-58a, 031-60a (Kardex is a card file mining claim information system located at the State of Alaska DNR Public Information Center in Fairbanks).

Reporter information

Type Date Name Affiliation Comment
Reporter 17-NOV-1999 J.M. Britton U.S. Geological Survey

Beyond USGS

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

Authoritative Alaska resources

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