A new cobalt(II) phosphate compd. has been synthesized using high-temp. flux methods in the CsCl/NaCl media at 650°C. The title compd., Na3CsCo7(PO4)6, forms vibrant purple plate crystals. It crystallizes in a monoclinic space group C2/c (no. 15) with the cell dimensions a = 12.844(3)Å, b = 10.764(2)Å, c = 15.630(3)Å, β = 113.54(3)°, and V = 1980.96(3)Å3. The X-ray single crystal structure reveals that the Co2+ cations adopt CoOn coordination, including square-planner (n = 4), square pyramidal (n = 5) and octahedral (n = 6) geometries. These polyhedra share corner oxygen atoms to form an extended three-dimensional network structure. The Co2 cations are magnetic ions, and the possible magnetic lattice can be viewed as being constructed by triangular lattices, see the structure below. In this presentation, we will discuss the results of solid state synthesis, crystal growth, structure anal., UV-Vis spectroscopy, and magnetic characterization of the title compd.