Lithophysa (Thundereggs) Photos
Cochise College
Photos of Rocks        Igneous Rocks
Virtual Geology Museum       Hall of Rocks
Geology Home Page
Roger Weller, geology instructor                       

wellerr@cochise.edu    copyright 2007

thunderegg-A

If the lithophysa occurs within an obsidian, as the obsidian breaks down and is eroded away,
the rounded structure is left intact and has been called a thunderegg.

Photo is copyright free for non-commercial educational uses. 
Just credit photo to R.Weller/Cochise College.

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