Unique Cork Card Case Made by Natural Cork Only Weight 42g Dimensions: 10cm x 6 cm x 2cm Material: Made by natural cork wood. Cork wood come from bark of cork oaks. When a cork oak reaches 25 years old, a 1 inch-thick layer of cork bark is harvested without damage to the tree. The bark of mature cork oak can be harvested every nine years. After sterilization, cork bark is pressed flat into a thin cloth.