Spotted: Swedish-based 15:21 is creating natural and biodegradable phone cases. The cases are made from cork, which looks like leather as it ages, according to the company.

Most phone cases are made from plastic, which is difficult to recycle. Cork is 100 percent biodegradable. It is also naturally water-resistant, the company says. Cork trees are not harmed when it is harvested.

The Swedish phone cases are also an effort to save Portugal’s cork forests. Traditional demand for cork has declined as wineries started to use more plastic corks and aluminium screw caps. “This sudden change of demand has resulted in a deforestation of cork oaks, [but] by inventing new commercial uses for cork, we support the survival of the cork forests,” the company said.

In addition to cork phone cases, 15:21 also makes cork passport holders and other accessories.