Jim-Montana Prospect, Chandalar Mining District, Yukon-Koyukuk Census Area, Alaska, USAi

Regional Level Types
Jim-Montana Prospect	Prospect
Chandalar Mining District	Mining District
Yukon-Koyukuk Census Area	Census Area
Alaska	State
USA	Country

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).
Location: 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.
Geology: 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 (Brosg
Workings: Claims staked in 1972 and 1975.
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).
Alteration: Calc-silicate(?).

Commodities (Major) - Cu, Zn; (Minor) - Ag, Pb
Development Status: None
Deposit Model: Zn-Pb skarn deposits(?) (Cox and Singer, 1986; model 18c)

Other Databases

Link to USGS - Alaska:	CH095

Other Regions, Features and Areas containing this locality

References