Cork is a natural material sourced from the phellem layer of the cork oak, or Quercus Suber tree. Cork is considered a sustainable material since it comes from a renewable resource and its production involves minimal waste or harm to the tree. It has a closed-cell structure and is made from a substance called suberin, making it naturally resistant to water, mold, mildew, and fire. Combined with its thermal and sound absorbing qualities, these properties, make cork suitable for use across commercial applications such as walls, ceilings, and resilient flooring products. While it is a highly elastic and compressible material, cork can be easily punctured and scratched, and also fades in direct sunlight. Cork comes in various types, including unprocessed or granulated.