I have about 10 of these shark teeth that have so far been labeled as Giant Thresher's, aka Alopias grandis. All of mine are from Calvert Cliffs; 7 non-serrated, 3 slightly serrated. All of the specimens I have, have recurved crowns, meaning, the crown bends over or leans over toward one of the shoulders, at some angle (see enclosed image as an example). I've never seen one where the crown is mostly, or completely erect or straight "up", implying perhaps that it would come from an Anterior fi