close up texture of chonchoidal fracture in black and white

abstract arrowhead art artistic black breakage brittle broken chonchoidal clean close concave concurrent curves curving detail displays dragon dragonglass edge flake fracture geologic geological geology geoscience glass half igneous knapp knapping large left lines lithic material mineral natural obsidian pattern rock scale sharp silica silicate silicates single specialty stone sweeping textural texture tiny tool undulations uneven volcanic white