| Basis for focus area |
District outline from USMIN location polygon ID00048. |
| Identified resources |
Indicated resources of antimony and gold; past production of antimony, gold, silver, and tungsten. |
| Production |
District produced intermittently from 1932 through 1992. Yellow Pine mine (1938-1991): 856,189 stu WO3, 40,257 short tons Sb, 479,517 troy oz Au, and 1,756,928 troy oz Ag; Hangars Flats (1928-1938): 67 stu WO3, 3,758 short tons Sb, 51,610 troy oz Au and 181,863 troy oz Ag (Becker and others, 2019); Meadow Creek mine (1932-1937): 24, 500 metric tons at 2.136% Sb. |
| Status |
Past mining; exploration and permitting (2021) for Stibnite Gold project (formerly known as Golden Meadows project) (Becker and others, 2019), an open pit gold-antimony mine with reclamation. Final EIS due out near end of 2021 by Payette National Forest. |
| Estimated resources |
Stibnite Gold Project: Combined Indicated Mineral Resources:115.2 million short tons (Mst) or 104.5 million metric tonnes (Mt) grading 0.048 troy ounces per short ton (oz/st) Au or 1.63 grams per metric tonne (g/t) Au, 0.077 oz/st (2.65 g/t) Ag, and 0.07% Sb; Aggregate Indicated Mineral Resources: 5.46 million oz (Moz) Au, 8.90 Moz Ag, and 155.2 million pounds (Mlbs) Sb; Combined Probable Mineral Reserves: 98.07 Mst (88.96 Mt) grading 0.047 oz/st (1.60 g/t) Au, 0.071 oz/st (2.43 g/t) Ag, and 0.07% Sb; Total contained metal in the Probable Mineral Reserves: 4.58 Moz Au, 6.96 Moz Ag, and 137.0 Mlbs Sb. Four deposits combined also contain additional Inferred Mineral Resources of 10.8 Mst (9.8 Mt) grading 0.032 oz/st (1.10 g/t) Au, 0.049 oz/st (1.67 g/t) Ag, and 0.04% Sb that is not utilized in the prefeasibility study and Combined Inferred Mineral Resources 347 koz Au, 523 koz Ag, and 9.5 Mlbs Sb. (Becker and others, 2019). |
| Geologic maps |
Stewart and others (2016), scale 1:24,000; White (1940), scale 1:9,700. |
| Geophysical data |
Inadequate aeromagnetic and aeroradiometric coverage. |
| Favorable rocks and structures |
Early Cretaceous metasedimentary strata and Idaho batholith rocks. |
| Deposits |
Yellow Pine mine (MRDS dep_id: 10217607; USMIN site ID: ID00001). |
| Evidence from mineral occurrences |
MRDS; USMIN. |
| Geochemical evidence |
See King and others (1994); Curtin and others (1974); Baldwin and Etheridge (2019); Etheridge (2015). |
| Geophysical evidence |
Unknown. |
| Evidence from other sources |
Becker and others (2019). |
| Comments |
From Wintzler and others (2022): The sequence of hydrothermal mineralizing events in the district starts with: 1) disseminated Au mineralization deposited from 70 to 56 Ma, associated with sulfidation and potassium metasomatism (Orogenic mineral system); 2) W deposition in scheelite veins and breccias that crosscut disseminated Au mineralization in granodiorite (Porphyry Co-Mo-Au mineral system); 3) formation of epithermal quartz veins with Au and Ag at 51.9 to 51.2 Ma; and 4) Sb mineralization in stibnite veins that crosscut older disseminated gold and tungsten mineralization (both Meteoric convection system, with Low sulfidation gold-silver and Low sulfidation antimony deposit types, respectively. |
| Cover thickness and description |
Exposed at the surface. |
| Authors |
Virginia S. Gillerman, Reed S. Lewis, Christopher A. Tate, Albert H. Hofstra. |
| New data needs |
Additional geology, petrography, geochemistry and geochronology to better see how antimony fits into deposit and district. Easier to do as mining progresses with collaboration with industry, lidar. |
| Geologic mapping and modeling needs |
1:24,000 scale geologic mapping. |
| Geophysical survey and modeling needs |
High resolution, Rank 1 aeromagnetic and aeroradiometric coverage. |
| Digital elevation data needs |
Lidar incomplete. |
