Kentucky is a good state for rockhounding. Aside from Kentucky’s enormous coal deposits, the state also has Kentucky agates, chert, concretions, flint, fluorite, galena, geodes, and fossils. Kentucky is famous for its many caves, including Mammoth Cave. In addition, meteorites have been recovered in 27 locations in Kentucky, including Bath, Bullitt, Livingston, Franklin, Allen, Carroll, Grant, and McCreary Counties.
State Rocks, Gemstones, Minerals, Fossils, & Dinosaurs
Rockhounding Tip: Knowing state rocks, gemstones, minerals, fossils, and dinosaurs often can be very useful information for rockhounders. Ordinarily, states with significant mineral deposits, valuable gemstones, fossils, or unusual or significant rock occurrences will designate an official state mineral, rock/stone, gemstone, fossil, or dinosaur to promote interest in the state’s natural resources, history, tourism, etc. Accordingly, such state symbols often are a valuable clue as to potential worthwhile rockhounding opportunities.
Kentucky Agate (2000)
Kentucky designated Kentucky Agate as its official state rock in 2000. Agate, is a crypto-crystalline form of quartz, which is a silicate mineral. In Kentucky, beautiful specimens of red, black, yellow, and gray banded agate have been discovered in Estill, Jackson, Powell, Madison, and Rockcastle Counties. These Kentucky agates are derived from the Renfro-Borden Formation of Early Mississippian age and can be collected along some river drainages where the Borden is exposed to weathering.
Gemstone: Freshwater Pearl (1986)
Kentucky designated freshwater pearl as its official state gem in 1986. Pearls are deposits of calcium carbonate (aragonite, calcite, or both) called nacre. Pearl (nacre) is not a mineral because it does not have a distinctive crystal structure and because it is formed by the action of a living organism. Because pearls have long been used in jewelry, however, they are considered gemstones. Pearls form around irritants (usually sand grains) within a pelecypod shell (usually clam, oyster, or mussel). Freshwater pearls are the state gemstones of both Kentucky and Tennessee. Natural freshwater pearls historically were found throughout the Mississippi and Tennessee River valleys.
State Mineral: Coal (1998)
Kentucky designated coal as its official state mineral in 1998. Kentucky ranks as one of the top three producers of coal in the United States, with 150 to 160 million tons of annual production. Coal is mined in two coal fields: the Western Kentucky Coal Field and the Eastern Kentucky Coal Field. Coal is mined because coal is a rock that burns. Most of the coal mined in Kentucky is burned to produce electricity at power plants.
Fossil: Brachiopod (1986)
Kentucky designated the brachiopod as its official state fossil in 1986. Brachiopods are marine invertebrates with two dissimilar shells. They are very common in Paleozoic strata (especially in Ordovician, Silurian, Devonian and Mississippian rocks in Kentucky). Shells may be replaced with either calcite or quartz. Generally, the fossils are less than two inches in width. Brachiopods are fossil shells, from animals that lived in ancient seas. Most are now extinct. Although they resemble clams, brachiopods were a different group of animals. Hundreds of different types of brachiopods can be found in Kentucky. Modern brachiopods live in the sea. Accordingly, because brachiopods can be found in rocks throughout Kentucky, we know that an ocean once covered the area now known as Kentucky.
State-specific rockhounding books (including the books listed here as well as other books), regional rockhounding site guides, and other helpful rockhounding resources are identified - by category - in the Books & Gear section of Gator Girl Rocks with a link to the Gator Girl Rocks Amazon Store where you may easily browse selected resources and securely place an order. Your order will benefit Charity Rocks!
The Kentucky Geological Survey (KGS) provides scientifically based information on Kentucky's geology and mineral and water resources.
The Kentucky Paleontological Society was founded in 1993 for the purpose of promoting interest in and knowledge of the science of paleontology. A newsletter is published monthly, and several field trips are arranged annually.
- Allan W. Eckert, Earth Treasures Vol. 2 - Southeastern Quadrant (1985; reprint in 2000).
- James Martin Monaco & Jeannette Hathway Monaco, Fee Mining & Mineral Adventures in the Eastern U.S. (2d ed. 2010).
- Kathy J. Rygle & Stephen F. Pedersen, Southeast Treasure Hunter's Gem & Mineral Guide (4th ed. 2008).
Museums of Interest to Rockhounders
Ben E. Clement
The Ben E. Clement Mineral Museum’s mineral collection includes specimens from throughout the world. Thousands of these minerals are from the mines of the famous Southern Illinois and Western Kentucky Fluorspar Region. The museum also houses an extensive display of the coal plant fossil Lepidodendron and petrified wood. In addition, the museum exhibits fluorescent specimens and gemstone carvings.
Louisville Science Center
The museum exhibits local fossils and minerals.
American Cave Museum
Horse Cave, Kentucky
Kentucky’s official karst museum showcases the natural history of caves. The Hidden River Cave is located on site.
Kentucky Coal Museum
The museum houses a diverse collection of artifacts exploring the early years of industrial coal mining in Kentucky.
The museum exhibits local minerals and fossils.
Places to Visit - Interesting Sites To See
Mammoth Cave National Park
Mammoth Cave, Kentucky
Mammoth Cave is the longest recorded cave system in the world with over 365 miles of explored passages.
Big Bone Lick State Park
Boone County, Kentucky
Pleistocene (ice age) megafauna fossils have been found at this site. Scientists believe that mammoths and other creatures were drawn to the site by a salt lick. The Park bills itself as "the birthplace of American paleontology” – a term that dates from the 1807 expedition by William Clark and his brother General George Rogers Clark. In 2002, the National Park Service designated Big Bone Lick State Park as an official Lewis and Clark Heritage Trail Site. The visitor’s center and museum features local fossils including a 1,000 pound mastodon skull.
Red River Gorge Geological Area
The Red River Gorge Geological Area is located within the Daniel Boone National Forest. The area features over 100 natural sandstone arches as well as sandstone cliffs waterfalls, and natural bridges. Kentucky’s Natural Bridge State Park is adjacent to the Red River Gorge Geological Area.
Blue Heron Coal Mining Camp (Mine 18)
Big South Fork National River & Recreation Area – South Central Kentucky
Mine 18 or Blue Heron is a former coal mining community (company town and coal mine) that ceased mining in 1962 but has been recreated and maintained as an interpretive history area in the Big South Fork National River & Recreation Area.
Carter Caves State Park
Olive Hill, Kentucky
The Carter County region has the highest concentration of caves to be found in any area of Kentucky. Two of the Park’s caves offer guided tours year-round, Cascade Cave and X-Cave.
Rockhounding Sites for Children & Families
The Fort Payne and Warsaw-Salem Formations of Mississippian age, which crop out in a general semicircle around the Outer Blue Grass and southward into Tennessee, are noted for their abundant geodes. In many places, creeks that drain these formations are filled with geodes, and several mineral varieties can be collected, particularly during low-water stages. Other locations for geode collecting include the tributaries of the Green River in south-central Kentucky and along ancient terraces of the Kentucky River. The Green River has produced some very large geodes (two feet in diameter) and countless smaller ones.
Concretions are formed by the deposition of distinct minerals, different from the surrounding rock, very firmly cemented around a nucleus. They are generally lens shaped, although some have irregular, complex forms. The most common cementing materials are calcite, siderite, and silica. Parts of plants and animals may serve as nuclei, and well-preserved fossils may be found in concretions. In Kentucky, large concretions of siderite and calcite, which used to be called ironstones, are found in shales associated with coal beds. Nodules are another type of irregularly shaped minerals that occur in sedimentary rocks. The most common minerals that occur in nodules are siderite, gypsum, calcite, quartz, and barite/celestite. Siderite nodules, concretions, and liesegang (iron-stained) banding are a very common type of mineralization found in eastern and western Kentucky sandstones.
Ordovician) & Minerals
Jefferson & Spencer Counties, Kentucky
Various fossils brachiopods, bryozoans, cephalopods, conodonts, corals, gastropods, monoplacophorans, pelecypods, scolecodont teeth, stromatoporoids, trace fossils, trilobites) and mineralized brachiopods, aulocerid stromatoporoids and colonial corals with calcite, dolomite, celestine and other minerals occur in interbedded shale and limestone in the Drakes and Grant Lake Formations in the road cuts on U.S. 421 north of Madison State Road 155 between Fisherville and Taylorsville, Kentucky.
Carroll County, Kentucky
Various fossils (brachiopods, bryozoans, cephalopods, conodonts, gastropods, graptolites, monoplacophorans, pelecypods, scolecodont teeth, trace fossils, trilobites) occur in shale with thin limestone layers in the Kope Formation in road cuts on State Roads 467 and 227 between I-71 and Worthville.
Bullitt and Nelson Counties, Kentucky
Various fossils (brachiopods, crinoids, sponges, cephalopods, trace fossils, trilobites) occur in the Waldron Shale and Laurel Limestone in road cut on State Road 245 between I-65 and Bardstown.