Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock. It is produced when felsic lava extruded from a volcano cools rapidly with minimal crystal growth. Obsidian is commonly found within the margins of rhyolitic lava flows known as obsidian flows.
from TurkeySIMILAR TO SEEN: The image shows an example of the single specimen you will receive. This will be picked from our stock box graded and with a size within the minimum and maximum size range indicated. It will not be the exact specimen in the photo, the colours, shape, size and style may vary as with any natural item.