Triangular Teeth

• If the blade is shaped like an isosceles triangle---like the side of a pyramid---and serrated like a steak knife on the two sides, and the blade is longer than the width of the root, you've got a tooth from a Great White shark.
  
  

Knife Blade

• If the tooth is long and slender, and reminds you of a knife blade, and has two tiny but sharp spikes near the base of the main blade, you have a Sand Tiger tooth.
  
  

No Serrations

• If the tooth isn't serrated, and the blade is shorter than the root is wide, you have a tooth from a Lemon shark.
  
  

Two-Part Tooth

• If the blade of the tooth seems to consist of two differently shaped parts--the front a serrated, backward-pointing blade, and the rear curved with deep serrations--you're looking at a tooth from a Tiger shark.
  
  

Bent Triangle

• If the tooth is triangular but one side seems slightly bent, the root and blade are about the same length and the blade is serrated, you probably have a Bull shark tooth.