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Old 03-17-2017, 11:47 AM
DrCube DrCube is online now
Join Date: Oct 2005
Location: Caseyville, IL
Posts: 6,526
Originally Posted by boffking View Post
I would look near volcanoes. Obsidian is a type of glass. What is the largest single piece of obsidian?
I would argue that a "pane" of glass is by definition man-made.