Bloodsoaked Chitin Fragment

Source
Bloodsoaked Chitin Fragment can be found at the back of Muckscale Grotto in the Dread Wastes and is one of the treasures of Pandaria.

As the flavor text indicates, it is a piece of Skeer the Bloodseeker that apparently was knocked loose, likely while he was battling the Muckscale saurok in the grotto during his questline.