The paper describes mineralogy of apatite-aegirine-mesoperthite pegmatites, which are located in a fenite halo at the southeastern contact of the Selyankino syenite block (Ilmeny State Reserve, South Urals). Two pegmatite veins are exposed by mines. The pegmatites differ from the known veins of the Ilmeny State Reserve in a high amount of apatite and the presence of the best collection aegirine druses. The pegmatites contain albite, microcline, aegirine, hydroxyapatite, fuorapatite, calcite, titanite, chevkinite-(Ce), magnetite, ilmenite, hematite, rutile, Fe and Mn hydroxides, monazite-(Ce), rhabdophane-(Ce), rhabdophane-(La), and dalnegorskite.
Keywords: aegirine, apatite, mesoperthite, dalnegorskite, syenite pegmatites, phenite, South Urals.
Received 14.03.2023, accepted 17.05.2023

E.P. Makagonov, South-Urals Federal Research Center of Mineralogy and Geoecology UB RAS, Miass, Chelyabinsk district,  Russia; mak@mineralogy.ru

S.А. Repina, South-Urals Federal Research Center of Mineralogy and Geoecology UB RAS, Miass, Chelyabinsk district,  Russia;

M.A. Rassomahin, South-Urals Federal Research Center of Mineralogy and Geoecology UB RAS, Miass, Chelyabinsk district,  Russia

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