Island Clouds are a special type of cloud. They are fluffy, but dense enough to carry all kinds of things, including people and even buildings. They form islands in the sky seas.
Island Clouds, as well as Sea Clouds, are created when a compound in Seastone called "pyrobloin" is ejected into the air by volcanic eruptions and comes in contact with water vapors. The density of the water vapors determines whether Sea Cloud or Island Cloud will be created. Both these types of clouds are not normally able to survive on the Blue Sea.
- One Piece Manga and Anime — Vol. 26 Chapter 240 and Episode 154, Pagaya explains creation of island and sea clouds.
- One Piece Manga — Vol. 32 Chapter 303, The cloud from Usopp's Milky Dial is shown to disperse after being released.
- One Piece Manga and Anime — Vol. 26 Chapter 240 and Episode 154, Pagaya talks about the factory.