Gyali is a Greek island and part of the island group Dodecanese in the Eastern Aegean Sea (36 ° 40 'N, 27 ° 7' O).
A volcanic eruption on the neighboring island of Nissiros threw pumice into the sea about 200,000 years ago. As a result, the pumice cooled down instantly and thus obtained its unique "pozzolanic" features. Later, the ocean bed lifted and the island of Gyali was formed.
The island consists of two connected hills and has a base area of approximately 4.5 km² (1,100 acres). The hill in the southwest of the island is about 180 m (600 feet) high and consists largely of pumice. All in all, the deposit has about 100 million tons of YALI® of highest quality.