Cork is the outer bark of the cork oak tree, Quercus Suber L, which grows mainly in the Mediterranean region of the world. The bark is a vegetal tissue composed of an agglomeration of dead cells filled with air and lined with alternating layers of cellulose and suberin.
The use of cork as a raw material dates back to the Phoenician and Greek times. Because of its use as wine bottle stoppers, cork began to be known all over the world. In fact, it is the only material that manages to make a perfect sealing during the ageing of the wine.
Today, cork represents for Portugal a valuable resource being one of the most important exporting products.