Photoluminescent and magnetic properties of lanthanide containing apatites: NaxLn10-x(SiO4)6O2-yFy, CaxLn10-x(SiO4)6O2-yFy (Ln = Eu, Gd, and Sm), Gd9.34(SiO4)6O2, and K1.32Pr8.68(SiO4)6O1.36F0.64.