Almarudite (IMA symbol: Alr) is an extremely rare alkaline manganese beryllium silicate mineral of the cyclosilicates (ring silicates) class, with the chemical formula , from the volcanic environment of the Eifel Mountains in Germany.http://www.mindat.org/min-25681.html MindatMihajlović T., Lengauer C.L., Ntaflos Th., Kolitsch U. and Tillmanns E. 2004: Two new minerals, Rondorfite, Ca8Mg[SiO4]4Cl2, and Almarudite, K([],Na)2(Mn,Fe,Mg)2(Be,Al)3[Si12O30], and a study of iron-rich Wadalite, Ca12[(Al8Si4Fe2)O32]Cl6, from the Bellerberg volcano, Eifel, Germany, Neues Jahrbuch für Mineralogie - Abhandlungen, 179, pp. 265-294;
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