A rare discovery was recently made by Mia Farlow while visiting her grandparents, Mary Jean and Skylar Burdette on their farm in far northwest Ringgold County.Mia, her brother Aidan and mom Andrea took a short walk on a dirt road in western Jefferson Township in search of Lake Superior agates in the glacial till soils. After a few minutes rock hunting Mia found a weathered piece of limestone with several ammonite fossil imprints.
On her visit to the road cut the next day, Mia found a small shark tooth.
A shark tooth in Iowa is a rare fossil, but not unheard of. Over the years several shark teeth have been found primarily in southeast Iowa. This shark tooth may be the first such find in Ringgold County.
Iowa has been covered by seas during two periods in earth's geologic past, the most recent being during the Carboniferous Period 290 to 360 million years ago. During that time numerous sharks swam in warm shallow seas covering Iowa that deposited limestone formations of the Mississippian and Pennsylvanian Age.
Mia's two fossil discoveries are from that ancient past. They were carried to that road cut by much more recent glaciation of the Pre-Illinoisan Glacial Period 500,000 to 2,500,000 years ago that have carved limetone formations to the north. The two fossils found that day were first depsoited somewhere north of Ringgold County and then scooped up by the glaciers to be deposited on that hillside for discovery in the fall of 2015.
The Burdettes were born and raised in the Diagonal area and have recently purchased land in Lincoln and Jefferson Townships, where they soon plan to retire.
Photographs courtesy of Mount Ayr Record-News
Transcription by Sharon R. Becker, November of 2015