Barite vein in central Kentucky.
Kentucky has numerous metallic and non-metallic mineral resources, including iron, titanium, phosphates, and vein minerals such as fluorite, barite sphalerite, galena, and calcite. Igneous intrusive rocks also occur in eastern and western Kentucky.
Vein mineral deposits occur in 20 counties in the central, western, and southern Kentucky mineral districts. Iron ore occurs in east-central Kentucky; titanium minerals in the Jackson Purchase Region; phosphates in the Blue Grass Region near Woodford County; and small igneous intrusions in the Western Kentucky Fluorspar District and in Elliott County.
The vein minerals consist of fluorite, barite/celestite, sphalerite, galena, calcite, and secondary alteration/oxidation minerals such as smithsonite, hemimorphite, cerussite, anglesite, pyromorphite, gypsum, and anhydrite. Hematite, limonite, and goethite are the dominant minerals found in iron ore. Rutile and ilmenite are titanium minerals, and a cryptocrystalline variety of apatite is an example of a phosphate.
The igneous rocks occurring in Kentucky are called peridotites and consist of minerals such as olivene, garnet, magnetite, ilmenite, and chromite. The Elliott County peridotite is a special type of igneous rock called kimberlite, which is the type of rock in which diamonds occur; but none have been found in Kentucky.
Iron ore was used for various steel products. Titanium can be used as a high-strength alloy in aircraft and ship building. Phosphates are used as fertilizer. Vein minerals such as fluorite and barite are used in the steel and oil-field industries, respectively. Sphalerite and galena are metallic minerals used in automobiles, electronics, and radiation protection.
Kentucky was a major center for mining iron, phosphates, barite, and fluorite during the early 1900's. Mines operated for several years, until larger deposits were discovered in other parts of the United States, making Kentucky's deposits uneconomic. Some of the earliest mining in Kentucky occurred in vein deposits near Gratz in Owen County, where lead was mined for bullets during the Revolutionary War. Occasionally, some of the vein mineral deposits are mined by small operators, but currently no mines are operating in any district. However, exploration activity has been conducted by major mining companies.
Western District. Kentucky was once the largest producer of fluorite in the United States. The Western Kentucky Fluorspar District was very active during World War II, when numerous mines were in operation in Livingston and Crittenden Counties. Numerous igneous dikes in the district are too small to be mined.
Central District. During the early 1900', numerous mines that produced vein minerals operated in central Kentucky. The Woodford County phosphate mines and the iron mines in east-central Kentucky were also active during this time.
Elliott County. Several attempts have been made to explore and mine the Elliott County igneous intrusion, but no production of any commodity has been authenticated.
Cumberland County. During the late 1970's a consortium of major mining companies exploring for zinc opened a 2,000-foot-deep exploration shaft in Cumberland County, but no actual mining was conducted.
Jackson Purchase Region. Titanium deposits that occur in the Jackson Purchase Region have never been mined because they are very low grade and discontinuous.
The primary revenue-producing commodities have been the vein minerals (fluorite, sphalerite, barite, galena, calcite), iron ores, and phosphates.
Contact Warren H. Anderson, Kentucky Geological Survey, 228 Mining and Mineral Resources Building, University of Kentucky, Lexington, KY 40506-0107, (606) 257-5500.