After a Quercus Suber tree, also known as Cork Oak, reaches maturity it's bark can be harvested every 8 to 9 years without harming the tree. The tree will then regrow it's bark.
 
Ever wonder where cork comes from? Well, now you know!
 
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* Photos show all sides.
* Sizes, shapes and colors my vary due to being a natural stone, being hand-carved and/or difference in computer monitors.