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Abstract. Natural samples of fluorite and apatite from granites, pegmatites, carbonatites and andesitic tuffs were investigated by steady-time spectroscopy to characterize the luminescence properties of Ce 3+ and Eu 2+ . The luminescence of Ce 3+ has been clearly seen in fluorite as 320 and 337 or 343 nm bands. In apatites, two distinct bands for two different Ca crystal sites were obtained: 340-380 nm for Ca(1) and 420-450 nm for Ca(2). The luminescence spectra of Eu 2+ in the fluorite crystals were measured even at for low concentration of this element (0.11 ppm). For Ce 3+ , it has been showed that the crystal field strength depends more on the nature of the ligand than on the Me-ligand distances.

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