Fluorcarmoite-(BaNa) is a rare phosphate mineral, belonging to arrojadite group, with the formula Ba[]Na2Na2[]CaMg13Al(PO4)11(PO3OH)F2.Cámara, F., Bittarello, E., Ciriotti, M.E., Nestola, F., Radica, F., and Bracco, R., 2015. Fluorcarmoite-(BaNa), IMA 2015-062. CNMNCNewsletter No. 27, October 2015, 1229; Mineralogical Magazine 79, 1229–1236 It is a barium-rich member of the group, as is arrojadite-(BaNa), arrojadite-(BaFe), fluorarrojadite-(BaFe) and an unapproved species ferri-arrojadite-(BaNa). The "-(BaNa)" suffix informs about the dominance of the particular elements (here barium and sodium) at the corresponding structural sites.Hatert, F., Mills, S.J., Pasero, M., and Williams, P.A., 2013. CNMNC guidelines for the use of suffixes and prefixes in mineral nomenclature, and for the preservation of historical names. European Journal of Mineralogy 25, 113-115
Arrojadite group The arrojadite group is defined in form of the complex, general formula A2B2CaNa2+xM13Al(PO4)11(PO3OH1−x)W2, where: A = large divalent cations (barium, lead, strontium) and vacancy ([]), eventually monovalent cations (potassium, sodium) B = small divalent cations (iron, manganese, magnesium) and vacancy ([]), eventually sodium M = Fe2+ (this gives the root name arrojadite) or Mn2+ (root name dickinsonite), or eventually Mg W = hydroxyl group or fluorine The two suffixes in the name correspond to A1 and B1 sites. Third suffix may be present in special cases.Chopin, C., Oberti, R., and Cámara, F. 2006. The arrojadite enigma: II. Compositional space, new members and nomenclature of the group. American Mineralogist 91, 1260-1270.
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