Having a crescentic outline and an area of about 1 km2 the Polumesyats intrusion is composed of coarse- and medium-grained arfvedsonite-riebeckite granites with a subordinate role played by fine-grained riebeckite granite and peralkaline granosyenites. Dykes of granosyenite porphyry and peralkaline granosyenite porphyry occur. The rocks are rich in accessories including zircon, orthite, monazite, thorite and fluorite.
Geological map of the USSR 1:200,000, 1960, Sheet M-43-XVII. NURLIBAYEV, A.N. 1973. Alkaline rocks of Kazakhstan and their ore deposits. Nauka, Alma-Ata. 296 pp.