Central Kentucky Mineral District

Region Central, South Central
Mineral systems
Deposit types
Critical minerals
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Outline of the Central Kentucky Mineral District.
Identified resources Historical production of barite, calcite, fluorite, lead, and zinc.
Production Unknown.
Status Past mining; exploration for deeper mineral potential in the Cambrian-Ordovician Knox Group has been conducted for several years and has yielded traces of metallic and nonmetallic minerals, although no commercial ore bodies have been discovered.
Estimated resources Unknown.
Geologic maps Complete geologic map coverage at 1:24,000 scale by the Kentucky Geological Survey.
Geophysical data Inadequate aeromagnetic and aeroradiometric data.
Favorable rocks and structures All veins cut through Ordovician carbonates along fractures and faults.
Deposits Lexington Quarry vein, Gratz mine (MRDS dep_id: 10106249), Twin Chimney fluorspar mine.
Evidence from mineral occurrences MRDS.
Geochemical evidence Veins contain barite, fluorite, calcite, sphalerite, galena, pyrite, chalcopyrite, and marcasite; some secondary carbonates including malachite, smithsonite, witherite, strontianite, and cerussite have also been observed or reported. Barite commonly contains high Sr, and strontianite and celestite is found with barite in some veins.
Geophysical evidence No data.
Evidence from other sources Documented mineralization (sphalerite, galena, barite, fluorite). The Lexington Quarry vein deposit was discovered during limestone quarrying and later mined for sphalerite during normal quarrying operations.
Comments Because the veins occur in carbonate rocks on the flanks of an intercontinental basin with little or no associated igneous activity, and are associated with solution-collapse features, they are considered Mississippi Valley-type deposits (Ohle 1980).
Cover thickness and description Surface to 200 ft.
Authors William M. Andrews, Gina Lukoczki.
New data needs Geochemical analyses, subsurface vein and deposit model.
Geologic mapping and modeling needs Not required.
Geophysical survey and modeling needs High resolution geophysical aeromagnetic and aeroradiometric coverage to determine underlying basement control on sedimentary cover mineralization.
Digital elevation data needs Variable lidar quality; some complete, some planned/funded, some inadequate.