Cork's elasticity, impermeability, and chemical stability means that it seals the bottle without contaminating the wine, even when it must mature for many years. The Romans also used cork for the soles of shoes and for floats for fishing nets.

What is cork made of? Cork consists of suberin cells in the shape of tiny pentagonal or hexagonal honeycombs, a complex fatty acid and filled with an air-like gas, which makes up 90% of its volume. It possesses an average density of around 200 kg/m3 and low thermal conductivity.

Auctions for wine corks sell in lots as small as 20 and as large as 500. The wine bottles usually sell for about 50 cents per bottle, but fancier bottles can fetch near $5.00 each (hint: Cobalt blue bottles!). Wine corks, however, generally sell for about 10 cents each.

In the early 21st century, the problem of cork taint became prevalent, leading many producers to stop using corks in favor of alternatives. Screw caps became especially prominent in Australia and New Zealand by 2010. Most cork was sourced from around the Mediterranean Basin, far from the Oceanian countries.