|MadSci Network: Chemistry|
The "glass" that you describe is actually a sheet of cane sugar! A saturated solution of sucrose [487 grams of sugar will dissolve in 100 ml of boiling water] is prepared and cast onto the same kind of paper [release paper] that 'stickers' come on. The water is allowed to slowly evaporate and a sheet of clear rock candy is left behind which is used to fabricate all the glass stunts you see in the movies special effects scenes. And....it is perfectly edible.....!
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