This small, circular complex is only 800 m in diameter. It consists of foyaite of two textural types. The first is homogeneous and consists of perthite, nepheline and pyroxene; the second is porphyritic with phenocrysts of nepheline several centimetres in diameter enclosing the other phases. There are some phonolite and tinguaite dykes and there are enclaves of ijolite in the foyaite. A few small dykes of rodbergite and brown carbonatite and sparse enclaves of white carbonatite also occur in the foyaite.