The popularity of cork as a stopper led to deliberate cultivation of cork trees, which prior to about 1760 had simply been harvested wherever they happened to grow.
The revolutionary crown cap—a metal lid lined with a disk of natural cork commonly known as a bottle cap—was invented in 1892.
Furthermore, it is fire retardant; flames will only char the surface, and no toxic fumes are generated.
However, no general substitute has been developed for cork that can be used in diverse applications.
Cork bottle stoppers have been found in Egyptian tombs dating back thousands of years.
Accounting for 30% of the existing trees, they produce half of the world's harvested cork.
A cork tree is ready for its first harvest when it is about 20 years old.
Cork is composed of dead cells that accumulate on the outer surface of the cork oak tree.
Because of its honeycomb-like structure, cork consists largely of empty space; its density (weight per unit volume) is one-fourth that of water.
Its low density makes cork useful in products like life preservers and buoys.
The large amount of dead-air space makes cork an effective insulation material for both temperature and noise.
For hundreds of years, Mediterranean cottages have been built with cork roofs and floors to keep out summer heat and winter cold—and to provide a soft walking surface.
Glass bottles were invented in the fifteenth century, but their use did not become widespread until the seventeenth century.
The Irish Examiner, formerly The Cork Examiner and then The Examiner, is an Irish national daily newspaper which primarily circulates in the Munster region surrounding its base in Cork, though it is available throughout the country.