Blue and green centers in natural apatites by ERS and optical spectroscopy data

Using ESR and optical spectroscopy we showed that the blue coloring is imparted to natural apatites by SO ₃ ⁻ radicals and the green coloring is due to SiO ₃ ⁻ radicals complexed with rare earth ions, SiO ₃ ⁻ -(Ce³⁺+K). The role of U⁴⁺ and Th⁴⁺ isomorphous actinide ions in the process of color center formation is investigated. United Institute of Geology, Geophysics, and Mineralogy, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Struktumoi Khimii, Vol. 36, No. 1, pp. 89–101, January–February, 1995. Translated by L. Smolina