How It's Made - 1372 Ultra Thin Glass

Standard materials such as lime, sand, soda, and pot ash...plus "smaller, secret ingredients...[to] enhance optical clarity and electrical conductivity"

There's a lot that's not being said there in those quotes.

The real payoff of this video is - to me, anyway - the thin, sagging ribbon of glass at 2:49 through 2:58 then the rolled-up glass at 3:25.

That's stunning.