I grew up on a farm outside Park City, Ky  that is at the Ste. Genevieve Limestone / St. Louis Limestone contact.  We spent many of a day picking up what the locals called "Bur Rock" from the tobacco field so we could plant.  The "Bur Rock" was the Lost River Chet which is very fossiliferous and is one of the things that got me into geology.

This is an example of one of the fossils that is very common in the Lost River Chert.  It is Bryozoan genus Fenestella.  The genus name is based on the Latin word fenestra which means window because of the window like openings in the skeleton of its colony.

Mississippian in age, specifically the Meramecian series 330 to 340 million years old

USA, Kentucky, Edmonson County - Self collected

76 grams (2.7 oz)

76 x 64 x 25 mm (3.0 x 2.5 x 1.0 inches)

• Kingdom: Animalia

• Phylum: Bryozoa

• Class: Stenolaemata

• Order: Fenestrida

• Family: Fenestellidae

• Genus: Fenestella