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 TurkeyACTUAL AS SEEN: The image shows the EXACT specimen you will receive. The specimen has been carefully hand selected and photographed. Measurements are as accurate as possible, though be aware measuring precise dimensions can be difficult from irregular shaped items. Whilst we portray colours as close to life-like as we can, colours will vary if taken in sunlight, indoors, from monitor to monitor and device to device. Once this specimen is sold, we will update this listing with new similar selected item, with a new photo and dimensions.