This image is of Notorhyncus primigenius fossil shark teeth on display at Mace Brown Museum of Natural History (August 2017). This extinct animal was also known as a seven-gill cow shark. It dates to the Pliocene Epoch (about 4.5 million years ago), Neogene Period. The fossils were found in Yorktown Formation, Beaufort County, North Carolina USA.
The Mace Brown Museum of Natural History is located at the College of Charleston, 202 Calhoun Street, 2nd Floor, Charleston, South Carolina 29424.
Learn more at their blog: http://blogs.cofc.edu/macebrownmuseum/