Corks are an unsurpassed sealant for kitchenware, laboratory glassware, masking, and various industrial applications. Impermeable and impervious to chemical interactions with liquid contents, the reusable cork is the perfect sealant. All of our corks are pressed, not amalgamated. Pressed is a more natural state and does not have the glue additives that agglomerated corks have. Unlike petroleum, gas, coal and other diminishing natural resources, cork is the outer bark that grows on replenish-able, renewable, inexhaustible evergreen oaks known by the Latin name Quercus (oak) Suber (cork). Almost 80% of the world's cork comes from the Iberian Peninsula - Portugal (51%) and Spain (28%) where soil, temperature, rainfall, and wind conditions are ideal. Like cows that continually renew their supply of milk or moose that regrow their antlers - the cork tree regenerates its precious outer layer 12 or 13 times during its 150 year lifetime. The outer bark is harvested every 8 to 10 years after the initial first stripping at 15 to 20 years