X-Nico

unusual facts about volcanic glass



Pozzolan

Volcanic ashes and pumices largely composed of volcanic glass are commonly used, as are deposits in which the volcanic glass has been altered to zeolites by interaction with alkaline waters.


see also

Coso Range

The prehistoric Coso inhabitants exported volcanic glass (Coso obsidian) and this highly valued toolstone has been found as far distant as the Channel Islands of California.