Gyali

Gyali island is a volcanic island of 4.6 square kilometers situated between the islands of Kos (south coast i.e. Kardamena) and Nisyros. It is part of the Dodecanese islands in the Aegean Sea. It is renowned for its pumice and if you ever get to pass by the island you will certainly not fail to notice the extensive pumice strip mining that is taking place, leaving Gyali island to a large extent quite barren of vegetation. On the other end of the island there are obsidian deposits which are also being mined. The island is very long, around 6 kilometers while its width ranges from 500 meters to 4 kilometers. Some remains of the Neolithic period have been found on the island, as well as an ancient burial ground. Although there are indications of metallurgical activity on the island of Gyali it is assumed that it was mainly used for farming during some parts of the year.

For more information you can check this link: https://en.m.wikipedia.org/wiki/Gyali