Bunker Hill Mine (Tyler; Stemwinder; Bunker Hill and Sullivan; Bunker Chance Mine), Bunker Hill properties, Kellogg, Coeur d'Alene District, Shoshone Co., Idaho, USA
|Latitude & Longitude (WGS84):||47° 30' 42'' North , 116° 8' 39'' West|
|Latitude & Longitude (decimal):||47.51167,-116.14417|
|Köppen climate type:||Dsb : Warm, dry-summer continental climate|
A former Ag-Pb-Zn-Au-Cu-Cd-Sb-Co-U-P (phosphoric acid) mine located in secs. 01, 02, 11, 12, 13, 14, 22, 23, 24 & 26, 048N, 002E, and in secs. 6, 16, 17, 18, 19, 29, 30, 31 & 32, T48N, R3E, BM. Discovered in 1885 by Noah S. Kellogg & his jackass. First produced in 1886. Operated during the periods 1886-1889, 1891-1981, and 1998-2001. Owned by Bunker Hill Mining Co. Inc. (see ownership details below). US Army Corps of Engineers awarded the contract to reclaim the entire site.
Leased and operated by the Helena Concentrating Co. (100.00%) (1885-1887); owned & operated by the Bunker Hill & Sullivan Mining & Concentrating Co. (100.00%), San Francisco, California (1887-1956); Owned & operated by the Bunker Hill Co. (100.00%), Kellogg, Idaho (1956-1968); owned & operated by the Gulf Resources and Chemical Co. (100.00%) (1968-1982); owned & operated by the Bunker LP (100.00%), Spokane, Washington (1982); and, leased & operated by the Bunker Hill Mining Co. (U.S.) Inc. (100.00%), Kellogg, Idaho (1987-1994).
The modern Bunker Hill mine property is an amalgamation over time of many mines. Some of these mines, including the Caledonia, Last Chance, Sierra Nevada, and Senator Stewart are described separately, as they occupy positions peripheral to the main Bunker Hill orebodies and were largely mined out prior to incorporation with the Bunker Hill Mine.The modern Bunker Hill mine property is an amalgamation over time of many mines. Some of these mines, including the Caledonia, Last Chance, Sierra Nevada, and Senator Stewart are described separately, as they occupy positions peripheral to the main Bunker Hill orebodies and were largely mined out prior to incorporation with the Bunker Hill Mine.
Mineralization is a Neoproterozoic polymetallic deposit (Mineral occurrence model informationL: Model code 85; USGS model code 22c; deposit model name: polymetallic veins; Mark3 model number 46) Neoproterozoic in age, hosted in Neoproterozoic quartzite of the St. Regis Formation, and in Neoproterozoic quartzite of the Revett Formation.
Individual orebodies may be galena (Pb) or sphalerite (Zn) rich with differing relative abundance of gangue and trace minerals. Local alteration includes sericitization, bleaching of hematite-bearing sediments and chloritization.
Specifics pertaining to the individual ore bodies:
Emery ore body: pinch & swell; strike 52SE; dip 52SE; thickness: 478 meters; length: 267 meters.
Francis ore body: pinch & swell; strike 58SE; dip 58SE; thickness: 537 meters; length: 212 meters.
Guy ore body: tabular; strike 53SW; dip 53SW; thickness 117 meters; plunge 35; width: 91 meters; length: 305 meters.
Hangingwall Tony ore body: tabular; strike 29SW; dip 29SW; width: 8 meters; length: 75 meters.
Lower Tony ore body: pinch & swell; strike 25-30SE; dip 25-30SE; thickness: 300 meters; width: 9 meters; length: 120 meters.
Mac ore body: pinch & swell; strike 35-40SE; dip 35-40SE; thickness: 600 meters; width: 2 meters; length: 370 meters.
March ore body: wedge; strike 42SW; dip 42SW; thickness: 610 meters; width: 61 meters; length: 305 meters.
Quill ore body: tabular; strike 42SW; dip 42SW; plunge: 34.
Stanley ore body: tabular; strike 48SW; dip 48SW; thickness: 400 meters; length: 152 meters.
Truman ore body: pinch & swell; strike 48SE; dip 48SE; thickness: 626 meters; length: 137 meters.
Upper Tony ore body: tabular; strike 32SW; dip 32SW; thickness: 90 meters; width: 4.5 meters; length: 60 meters.
West J ore body: pinch & swell; strike 35-45S; dip 35-45S; thickness: 366 meters; length: 427 meters.
There are dozens of orebodies in the deposit, only the larger ones are noted above. Economic deposits are of two types: (1) massive wedge-shaped or tabular open-space filling and replacement veins along faults and larger extension fractures striking NW to EW and dipping SW; (2) Closely spaced fracture fillings near NE to EW striking SE or S dipping faults forming pinch-and-swell veins (locally called Jersey or Link-type Veins). Sporadic stratiform mineralization throughout the mine is not economic. The largest orebody, the March, is a pipe-like triangular, prism-shaped replacement body at the intersection of the Cate and Dull faults.
Zone of disseminated siderite extends 10's to 100's of meters out from the veins, passing into a siderite-ankerite zone up to 10's of meters wide, and then into a zone of ankerite-calcite 100's of meters wide. The deposit is at least partly oxidized down to about 600 meters depth, presumably along major faults. Shallow orebodies mined in the 1880's to early 1900's were largely oxidized with cerussite as the principal ore mineral.
Controls for ore emplacement:
Ore control descriptions: Ore bodies occur mostly in upper Revett Formation consisting of about 50% massive quartzite interlayerd with thin-bedded sericitic quartzite, silitite, and argillite.
Ore control descriptions in the NW part of the mine: Most ore is in the hanging wall of the Cate Fault; whereas, in the SE part, most ore is in the footwall of the Cate Fault.
Ore control descriptions Structural controls are significant and of many varieties. Principal control is the intersection of two general fault and fracture sets (NW and NE) within the overturned northern limb of a WNW trending anticline. Major replacement orebodies, such as the March, occur at the intersection of the Cate Fault with branching faults. NE striking Link veins are hosted by faults that connect the Cate with its various branch faults. Hinges of parasitic flexures on the anticlinal limb contain crackle zones that are an important control for the Quill and similar zinc orebodies.
Local rocks include Argillite, siltite, and quartzite; Middle Proterozoic Ravalli Group; northern Belt Province.
Workings include underground openings. Total development is reported at a length of 208,000 meters. The overall depth is 1,402 meters. The Kellogg Adit is 3,350 meters long and is the main mine access. Other sources estimate total workings at more than 240,000 meters. The Bunker Hill mine used several mining methods, including square sets, top slicing, room and pillar, and block caving.
Production statistics: Year: 1983; period: 1887-1981: 35,457,348 metric tions of ore mined. Major smelter recovery was Ag: 4,080 metric tons at 157 grams/ton.
Year: 1991; period: 1988-1991: 756,652 metric tons of ore mined. Major commodity was Pb: in concentrate Pb 12,135 metric tons: 2 weight per cent.
34 valid minerals.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
1000 - 1600 Ma
Age: Mesoproterozoic (1000 - 1600 Ma)
Stratigraphic Name: Ravalli Group
Description: Feldspathic quartzite and subordinate siltite and argillite of the Burke, Revett, and St. Regis formations in northern Idaho; south of St. Joe River, includes correlative garnet-grade quartzite and schist. (Mesoproterozoic Belt Supergroup).
Reference: Horton, J.D., C.A. San Juan, and D.B. Stoeser. The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. doi: 10.3133/ds1052. U.S. Geological Survey Data Series 1052. 
1000 - 1600 Ma
|St. Regis Formation|
Age: Mesoproterozoic (1000 - 1600 Ma)
Reference: Zientek, M.L., P.D. Derkey, R.J. Miller, J.D. Causet et al. Spatial Databases for the Geology of the Northern Rocky Mountains - Idaho, Montana, and Washington. U.S. Geological Survey Open-File Report 2005-1235 Version 1.0.