Calcite is the most common mineral in sedimentary rocks. The best examples of crystals occur in pockets that geologists call “vugs.” They also occur in quartz-lined geodes, in fractures (where free crystals are usually rare). Finally, they can be found in mineralized areas associated with faulting where they occur in veins.
Calcite is associated with some metamorphic and igneous rocks where they occur in late-forming deposits where voids occur. Those aren’t in the Ohio Valley and won’t be covered further.
Quarries and roadcuts provide good access to specimens whenever conditions are “just right” for vugs to form. Not every limestone quarry is a source for good crystals, but most quarries have something.
The gallery below will describe specimens from my collection (not for sale) with a geological story. Many of these specimens will ultimately be donated to the Indiana State Museum for Indiana specimens and the Cincinnati Museum Center for other locations except the western Kentucky portion of the fluorspar district. Unfortunately, Kentucky holds no natural history museum. The only locations in-state are the Geological Survey and the Clement Mineral Museum (for fluorspar district specimens).
Corydon Quarry, Harrison Co., Indiana – currently managed by IMI (Irving Materials, Inc.) the quarry is closed to collectors. It has operated northwest of Corydon since the late 1940s. I first visited the quarry in 1969, then again the the late 1970s – 2000, and sporadically after that. Quarry photos will be posted on the Geological Scenes album. Rock quarried is the from the top of the St. Louis Limestone in the bottom of the pit through the entire Ste. Genevieve Limestone & Paoli Limestone. The top of the quarry includes Chester-age (Upper Mississippian) Mooretown Sandstone / Bethel Shale with a thin but persistent coal seam, Beaver Bend Limestone rich in fossils.
Harrodsburg Road Cuts, Monroe Co., Indiana – a famous area for geodes with many minerals include nice calcite crystals that sometimes have millerite inclusions,
Salem Quarry, Washington Co., Indiana – Hanson Aggregates closed the quarry several years ago. This quarry was in the Harrodsburg and Salem Limestones, Middle Mississippian age. The quarry is famous for geodes with large celestine crystals, but also has beautiful calcite, too.
Salem Road Cuts, Washington Co., Indiana – has geodes with calcite and other minerals.
Roadcuts near Owingsville, Bath Co., Kentucky – have limestone vugs in a shale (possibly stromatoporoids). Dominated by brown scalenohedral calcite, a late generation transparent calcite may be perched on the crystal tips; other minerals include dolomite, barite, goethite, & pyrite.
Albany Quarry, Clinton Co., Kentucky – Gaddie-Shamrock / Caldwell Stone – collected by Steve Garza, has a variety of minerals including calcite, dolomite, fluorite, gypsum (selenite) and sphalerite.
Bardstown Quarry, Nelson Co., Kentucky – now closed, was operated by Medusa Aggregates they Nalley – Hayden, then as the Cedar Creek Quarry. The only strata mined was the Laurel Dolostone, Silurian-age. The quarry was famous for complete trilobites and Devonian fossils in the residual soil. Operations ran out of property to mine and was recently sold for development. A new quarry has been opened about five miles away, but I haven’t visited it yet.
Danville Quarry, Boyle Co., Kentucky – Caldwell Stone Company, operating for more than 90 years, mines the Lexington Limestone. Has a vein running through the quarry with fluorite, calcite, barite, and other minerals. The largest collected calcite crystal weighed more the 300 lbs. I’ve collected 18″ crystals that we so etched they are yard decorations.
Flemingsburg Quarry, Fleming Co., Kentucky – operated by Hanson Aggregates, is known for calcite in simple rhombic crystals. The Ordovician limestone contains oil and the calcite sometimes is coated in dried oil.
Georgetown Quarry, Scott Co., Kentucky – Nalley & Gibson Quarry, mostly underground. Mines through the Thomas Vein of the Central Kentucky Mineral District. Ordovician Lexington Limestone is mined.
Irvington Quarry, Breckinridge Co., Kentucky – currently managed by Liter’s Quarry, it was Kentucky Stone Company quarry for a long time. Rock quarried is the Mid to Upper Mississippian Ste. Genevieve Limestone. Quarry has upper and lower pits and has been operating since the 1940s.
Lebanon Quarry, Marion Co., Kentucky – managed by Nalley & Hayden. Now operating its third pit, the first has been abandoned for several decades. The second closed a couple of years ago. That’s the pit I visited on several occasions. The rock contains oil from the overlying New Albany Shale and the calcite sometimes is coated in dried oil. The upper part of the quarry is the Boyle Limestone (Devonian) somewhat dolomitized and brecciated.
Lockport Quarry, Henry Co., Kentucky – managed by Liter’s Quarry, this underground quarry encounters the Lockport vein in the Central Kentucky Mineral District. I’ve had several visits that were quick productive.
Illinois – Kentucky Fluorspar District – includes a number of mines in Hardin & Pope Co., Illinois and Crittenden & Livingston Co., Kentucky.