1997 Volume 46 Issue 4 Pages 265-270
The fluorescence spectra and luminescent properties of Kimuraite [CaY2(CO3)4·6H2O, rhombic, Bizen-cho, Higashimatsuura, Saga pref.] were investigated by a three-dimensional contour-plot method. From the results, the strongly reddish-purple fluorescence of the mineral under ultraviolet light was found to depend on the following fluorescent rare-earth(III)ions. Eu(III), Tb(III), Dy(III), and Gd(III). These rare-earth(III)ions in the mineral showed many sharp excitation and emission bands. The bands of the luminescence of Kimuraite could be attributed to the f-f allowed transition of Eu(III): Ex. 395 nm (7F6→5L6)/Em. 615 nm (5D0→7F2); Tb(III): Ex. 380 nm (7F6→5D3)/Em. 545 nm (5D4→7F5); Gd(III): Ex. 275 nm (8S7/2→ 6D3/2)/Em. 312 nm (6P7/2→8S7/2);Dy(III): Ex. 352 nm/Em. 575 nm (4F9/2→6H13/2), respectively.