There has been an extensive interest in cryst. solids contg. magnetic nanostructures. The chem. systems that we have paid special attention to thus far in our lab. include transition-metal-contg. oxy compds., such as silicates, phosphates and arsenates. The oxy anions, like org. ligands, serve as closed-shell, nonmagnetic "chelating" agents that structurally isolate the transition-metal-oxide nanostructures. This provides electronic confinement for the study of spin-spin and spin-orbital interactions of fundamental and technol. importance. We have recently synthesized a new iron (III) phosphate compd. using high-temp. flux methods in molten salt media. The title compd., μ3-Na5Ba10Fe7O2(PO4)14, crystallizes in a trigonal space group, P-3m1 (no. 164). The X-ray single crystal structure reveals that the Fe3+ cations adopt FeOn coordination, including square pyramidal (n = 5) and octahedral (n = 6) geometries. Three FeO5 square pyramids share a corner oxide anion, μ3 oxo-, and, in turn, create magnetic equilateral triangles that are structurally confined from one another by the nonmagnetic oxyanion, (PO4)3-. The temp.-dependent magnetic measurements have revealed that this solid has a ferromagnetic anomaly at high temps. (Tc textgreater 300K). The subsequent field-dependent studies at temps. near Tc (T = 300K) have shown magnetic hysteresis. In this presentation, we will show the results of solid state synthesis, crystal growth, structure anal., UV-Vis spectroscopy, magnetic characterization and heat capacity measurements.