These arrowheads are knapped from mahogany obsidian glass. Shapes and sizes vary, average length 1"- 2" x width 1/2" - 3/4" and are pulled at random. I have a few pictures above of different arrowheads to show how they can vary slightly in shape and size being that they are natural, you will receive one similar to the ones shown above. This is a craft grade arrowhead, one side is beveled and the other is flat. The necklace closing is a chain with lobster clasp, allowing you to slightly adjust it in length.