I know, I read the whole thing. Glass is also made of limestone, fyi. 1) Oil was less expensive, inflation-adjusted, in 1994 than it is today ($30/bbl) 2) Only

I know, I read the whole thing. Glass is also made of limestone, fyi. 1) Oil was less expensive, inflation-adjusted, in 1994 than it is today ($30/bbl) 2) Only very specific sand is in short supply today (construction and fracking sand, neither of which is fungible with arbitrary sand) 3) Glass is made of natural gas.