This is a very large fossil broad-toothed mako (Isurus hastalis) tooth from the Hawthorn Formation. It was collected in South Carolina after it eroded out of the Hawthorn Formation. This dates back to the Miocene (~2.6 to 15 Million years), found in South Carolina, USA. in the Hawthorn Formation.
 
This tooth has great enamel, shows fantastic patina and is sharp at the tip. This large tooth measures 1.97 inches!