Delaware Chert associated with the Delaware Limestone Formation occurring as nodules, lenses and stringers in Ohio. It is commonly found in riverbeds along the Franklin - Delaware county lines in Ohio, but may be found from Lake Erie into Columbus. Commonly found along the Scioto River, Franklin County, Ohio. Most commonly found in Defiance, Delaware, Erie, Franklin, Lucas, Marion, Paulding, Pickaway, Sandusky, Seneca, Wood Counties. Ohio. Delaware Chert is a local chert and is abundant.