Tolstoi Creek

Prospect, Inactive

Commodities and mineralogy

Main commodities Au
Other commodities Cu; Hg; Nb; Ta
Ore minerals chalcopyrite; cinnabar; gold; ilmenite; ilmenorutile; magnetite
Gangue minerals dravite

Geographic location

Quadrangle map, 1:250,000-scale ID
Quadrangle map, 1:63,360-scale D-2
Latitude 62.98249
Longitude -156.99724
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect at an elevation of about 1,400 feet on an unnamed tributary of Tolstoi Creek. It is about 1.0 mile north of hill 2008 and about 0.4 mile southwest of the northeast corner of section 2, T. 33 N., R. 41 W., of the Seward Meridian. The location is accurate.

Geologic setting

Geologic description

The Tolstoi Creek prospect is a black-sand-rich gold placer that contains visible gold, abundant magnetite, ilmenite, less abundant ilmenorutile, a Nb-Ta mineral, cinnabar, tourmaline (variety dravite), and a trace of chalcopyrite (Bundtzen, Cox and Veach, 1987). The creek is about 30 feet wide and is incised in glacial moraine of late Pleistocene age. The alluvium is poorly sorted; most of the gold and heavy minerals occur in sand and gravel that is interstitial to erratic boulders that originated in the Beaver Mountains (Bundtzen and Laird, 1980). The placer gold is mostly fine-grained with occasional grains to 5 mm across. Six pans collected at intervals across the creek contained from 1 to 5 grains of gold per pan (Bundtzen, Cox and Veach, 1987). The average fineness of the placer gold as determined by fire assay is 891. One placer concentrate contained 214 parts per million (ppm) niobium 14 ppm tantalum, 8.1 ppm gold, and 1.0 ppm silver (Bundtzen, Cox, and Veach, 1987).
Geologic map unit (-156.999599341598, 62.9818379570869)
Mineral deposit model Placer Au deposit (Cox and Singer, 1986; model 39a).
Mineral deposit model number 39a
Age of mineralization The prospect is in reworked, glacial moraine of Late Pleistocene (Wisconsin?) age and the placer is either late Pleistocene or Holocene in age (Bundtzen, 1980 [GR 63]).
Alteration of deposit None.

Production and reserves

Workings or exploration Placer occurrences in this area were prospected during the early part of the 20th century (Mertie, 1936). The placer was sampled by the Alaska Division of Geological and Geophysical Surveys in the 1980s (Bundtzen, Cox, and Veach, 1987).
Indication of production None
Production notes No known production.



Reporters T.K. Bundtzen (Pacific Rim Geological Consulting, Inc.), M.L. Miller (U.S. Geological Survey); and C.C. Hawley (Hawley Resource Group)
Last report date 5/11/2003