In the "New Mineral Names", by Ercit et al. 2007, in Am. Min. vol. 92 (page 1539) there is an abstract of Rastsvetaeva et al. (2006) article, where they describe an "apparently new member of the eudialyte group" and call it "eudialyte 3248",
The formula is:
Na
29Ca
12Zr
6[Si[sub]48[/sub]O
132(O,OH)
12]{[Na]
4[Si]
2}{[Mn]
3[Mn,Nb,Ti]
2}(OH,H
2O,Cl)
10
The mineral comes from the Lovozero massif.
Regards,
Luke K.