Flakes are a great choice for any level of knapper. Most of our flakes can easily be worked with a pressure a flaking technique, while some may require some percussion. Obsidian is a volcanic glass that is found in the western USA and Mexico. It's well known for its ease of work ability thus making it a great choice for any skill level knapper. Your purchase will contain 10lbs of Mixed obsidian flakes that range from 2-4 inches long and are a great choice for the beginner to expert knapper. Stone shown in the picture is an example of what to expect. Actual pieces may very. Skill Range: Beginner to Expert.