Denton Mine, Harris Creek Sub-District, Hardin Co., Illinois, USA
|Latitude & Longitude (WGS84):||37° 34' 15'' North , 88° 13' 12'' West|
|Latitude & Longitude (decimal):||37.57087,-88.22003|
|Other regions containing this locality:||Illinois-Kentucky Fluorspar District, Illinois/Kentucky, USA|
|Köppen climate type:||Cfa : Humid subtropical climate|
The Denton Mine a former Ba(baryte)-fluorspar-Pb-Zn-Ag mine, operated by the Ozark-Mahoning Company between late 1979 and 1993. Although the Denton Mine had 7 shafts (Denny and Seid, 2014) the main shaft was located in sec. 9, T11S, R9E, SW¼, approximately 6.5 miles north of the town of Cave-in-Rock (Samson and Masters, 1990, Denny et al., 2013). Local rocks at the mine include the Lower Chesterian (Glen Dean – Renault) Series.
The main ore body of the Denton Mine has a depth-to-top of 191 meters and is a typical tabular replacement/ bedding replacement/stratiform deposit (Lillie, 1988, Goldstein, 1997) and shows similarities to the ore in the Cave-in-Rock Sub-district. According to Denny et al. (2013, p. 8) the ore followed northeast-southwest fractures and extended to the southwest into sec. 17, NE ¼. Like other similar deposits near the Denton Mine, the primary mode of origin of the minerals was hydrothermal activity and lead, zinc and silver were by-products of fluorspar mining here.
The ore and specimens from the Denton Mine are mainly from the Rosiclare Level and the Sub-Rosiclare Level, but some mineralization did occur at the Bethel Level as well (Denny et al., 2013). Like other mines in the district, the primary method of extraction of the ore was room and pillar. Production statistics for 1983 was 43,660 metric tons of ore; 1984 was 42,407 metric tons of ore; 1985 was 54,312 metric tons of ore and in 1986 was 60,343 metric tons of ore.
One of the more notable finds of the Denton Mine included the Bahama Ore Body, which was discovered by drilling cross sections of diamond drill holes at near right angles to the main Denton Mine trend. The Bahama Ore Body was relatively small and narrow, but rich enough to warrant driving a drift. The Bahama Ore Body was affectionately named because it was south of the main trend and according to Ross Lillie “on its way to the Bahamas”. The ore discovered here was mined both in the Rosiclare and Sub-Rosiclare Horizons (Lillie, 2010).
One of the hallmarks of the Bahama Ore Body were beautiful deep golden calcite crystals showing a wonderful glassy luster. Single crystals of 30 cm were found in cavities that measured up to 8 meters in length. Specimens from the Bahama Ore Body were mined between 1991 – 1993 (Lillie, 2010). Purple fluorite cubes were also found here.
Along with the Minerva #1 (Ozark-Mahoning #1) mine and the Annabel Lee mines, the Denton was among the most productive fluorspar mines during the last phase of mining in the Southern Illinois Fluorspar District in the 1980s and 1990s. Along with the nearby Annabel Lee Mine, it is considered part of Harris Creek District.
7 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
330.9 - 346.7 Ma
|Lower Pope Group (Aux Vases Sandstone through Glen Dean Limestone)|
Age: Mississippian (330.9 - 346.7 Ma)
Stratigraphic Name: Renault Limestone; Yankeetown Sandstone; Paoli Limestone; Downeys Bluff Limestone; Bethel Sandstone; Paint Creek Formation; Ridenhower Formation; Cypress Sandstone; Beech Creek Limestone; Golconda Formation; Hardinsburg Sandstone
Comments: According to the stratigraphic column, the Pope Group only occurs in southern Illinois (south of 40 degrees north latitude). The lower part of the Pope Group is comprised, from oldest to youngest, of the Aux Vases Sandstone (0-160’), Renault Limestone (0-40’) and Yankeetown Sandstone (0-105’) [which together are equivalent to the Paoli Limestone (0-120’, includes the Levias Ls, “Lower Renault”, Shetlerville Ls, and “Benoist”)], Downeys Bluff Limestone (includes “Upper Renault”), Bethel Sandstone (0-110’), Paint Creek Formation (0-150’) and equivalent Ridenhower Formation (0-150’, includes “Paint Creek sand” and Sample Ss), Cypress Sandstone (0-200’, includes “Weiler/Kirkwood”), Beech Creek Limestone (0-40’, includes “Barlow”), Golconda Formation (0-180’, includes Big Clifty Ss – “Jackson sand”, Fraileys Sh, and Haney Ls – “Golconda lime”), Hardinsburg Sandstone (0-180’), and Glen Dean Limestone (0-110’). [Oil well drillers' terms shown in quotation marks.]
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. 
Finger, G. C., Risser, H.E., and Bradbury, J.C. (1960) Illinois Fluorspar, Illinois geological Survey Circular 296: 36.
Bradbury, J. C., Finger, G.C., and Major, R.L. (1968) Fluorspar in Illinois, Illinois Geological Survey Circular 420: 64.
Grogan, R. M., and Bradbury, J.C. (1968) Fluorite-Zinc-Lead Deposits of the Illinois-Kentucky Mining District, in: Ore Deposits of the United States, edited by John D. Ridge, A.I.M.E., New York, volume 1, 1st. edition: 370-399.
Pinckney, D. M. (1976) Mineral Resources of the Illinois-Kentucky Mining District, United States Geological Survey, Professional Paper 970: 15.
Lillie, R.C. (1988) Minerals of the Harris Creek Fluorspar District, Hardin County, Illinois. Rocks and Minerals: 63 (3): 210-226.
Koellner, M.S. (1987) A study of the fluid inclusion, stable isotope and mineralogical characteristics of the Denton fluorspar deposit, Cave-in-Rock, Illinois. Master’s Thesis, Iowa State University: 110.
Lasmanis, R. (1989) Galena from Mississippi-Valley type deposits. Rocks and Minerals: 64 (1): 11-34.
Sampson, and Masters, J.M. (1990) Directory of Illinois Mineral Producers, 1988-1989, Illinois State Geological Survey, Illinois Mineral Notes 103: 44.
Spry, P.G., Koellner, M.S., Richardson, C.K, and Jones, H.D. (1990) Thermal changes in the ore fluid during deposition at the Denton Mine, Cave-in-Rock Fluorspar District, Illinois. Economic Geology, Bulletin of the Society of Economic Geologists: 85: 172-181.
Williams-Jones, A.E., Schrijver, K., Doig, R., and Sangster, D.F. (1992) A model for epigenetic Ba-Pb-Zn mineralization in the Appalachian thrust belt, Quebec; evidence from fluid inclusions and isotopes. Economic Geology: 87 (1): 154–174.
U.S. Bureau of Mines (1995) Minerals Availability System/Mineral Industry Location System (MAS/MILS), U.S. Bureau of Mines Special Publication 12-95: file #0170690144.
Goldstein, A. (1997) The Illinois-Kentucky Fluorspar District. The Mineralogical Record: 28 (1): 3-49.
USGS (2005), Mineral Resources Data System (MRDS): U.S. Geological Survey, Reston, Virginia, loc. file ID #10082972 & 10144653.
Lillie, R.C. in Sadlocha, S. (2010), The Bahama Ore Body (see link below).
Denny, F.B, Devera, J.A., and Kittler, A. (2013) Bedrock Geology of Saline Mines Quadrangle, Gallatin and Hardin Counties, Illinois. Illinois State Geological Survey, Illinois Geologic Quadrangle Map, IGQ Saline Mines-BG: 1-10.
Denny, F.B, and Seid, M.J. (2014) Bedrock geology of Hardin County, Illinois. Illinois State Geological Survey, scale 1:48000: 2 sheets.