Microfossils of the Salem Limestone (aka Indiana Limestone) that existed in the Middle Mississippian Period (340-335 million years ago). Sections of this limestone quarried near Bloomington and Bedford Indiana were used as material for famous buildings around the United States. Buildings such as New York City's Empire State Building & Rockefeller Center and Washington's Pentagon & National Cathedral. One can learn more about the role of Salem Limestone in the building of the United States in Chapter 6 of the book Stories in Stone: Travels Through Urban Geology by David B. Williams.
Fossils found in Washington County, Indiana.