Gyali (Greek Γυαλί "glass", also spelled Yiali or Yali) is a volcanicGreekisland in the Dodecanese, located halfway between the south coast of Kos (Kardamena) and Nisyros. It consists of rhyolitic obsidianlava domes and pumice deposits. The island has two distinct segments, with the northeastern part almost entirely made of obsidian and the southwestern part of pumice. These are connected by a narrow isthmus and beach made of modern reef sediments.
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