Citation: Ertl, A.; Rossman, G. R.; Hughes, J. M.; Prowatke, S.; Ludwig, T. (2005). Mn-bearing "oxy-rossmanite" with tetrahedrally-coordinated Al and B from Austria: Structure, chemistry, and infrared and optical spectroscopic study Sample: REDT4 Reported formula: (Na.46 Ca.01) (Al2.35 Li.32 Mn2+.28 Fe2+.04 Ti4+.01) Al6 (Si5.51 Al.25 B.24) O18 (BO3)3 [(OH)2.80 O.20] [O.86 (OH).10 F.04] Tourmaline. American Mineralogist, 90, pp. 481-487.