On the key of an unpublished map of Di Paola (1976) this volcano, covering about 18x12 km, is shown as comprising "..pantelleritic ignimbrites associated with mugearitic-alkali and peralkaline trachytic central volcanoes." It has a radial dyke swarm (Mohr, 1980). Mohr (1966a) links it with Chilalo (No. 42) as a "trachyte-carbonatite volcanic centre", but now considers the carbonate rocks are not carbonatitic (P.A. Mohr, pers. comm. 1995). A mugearite described in Le Bas and Mohr (1968) contains aegirine-augite.
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