These two hemipristis or snaggle shark teeth have good serrations and a nice jet black color.

The Hemipristis serra or more commonly known as the Snaggletooth shark roamed the ancient oceans with the megalodon shark, sperm whales, and other ancient creatures.
There is a modern day snaggletooth shark but it's ancient ancestor was much larger, and much more ferocious.
These hemipristis teeth have a distinct shape and due to the large serrations in relation to the overall tooth size look rather fierce and menacing.