Devon Island (Nunavut), located in the Northwest Passage, is part of the Canadian Arctic Archipelago. It is the largest uninhabited island in the world. Mainly composed of gneiss and shale, the largest part of the island is a plateau of an altitude of 984 to 1,642 ft (300 to 500 meters) made of frost-shattered stones and almost devoid of plants and animal life. The eastern third of the island is covered by an ice cap whose maximum thickness varies between 1,642 and 2,296 ft (500 and 700 meters.