A specimen from a sill forming the small island of Hvalroso, southeast of Sabine O, has been described by Tyrrell (1932, p. 525 - referred to as Walrus Island). The rock is an olivine essexite of labradorite, augite, olivine, red-brown biotite and magnetite, with groundmass alkali feldspar, probable nepheline and abundant analcime.
TYRRELL, G.W. 1932. The petrography of some Kainozoic igneous rocks, and of the Cape Parry alkaline complex, East Greenland. Geological Magazine, 69: 520-7.