Cork is good

The Carbon Footprint of Wine Closures

Natural cork with PVC capsule: 11.2 tons of CO₂ per million units

Fake cork with PVC capsule: 24.7 tons of CO₂ per million units

Screwcap from 70% recycled aluminum: 35.9 tons of CO₂ per million units

Glass bottle: 183 tons of CO₂ per million units

[Reported in Decanter, Nov. 2007, p. 45.]