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As an alternative way of examining the prospects of the trivalent manganese ion as a luminescent centre in glasses, AI203:Mn , ZnAI204:Mn and LaAIO3:Mn were investigated by means of spectrofluorometry. The luminescent species identified were divalent and tetravalent manganese and impurities (chromium), whereas trivalent manganese did not show luminescence at wavelengths ~ 800 nm in LaAIO3:Mn and ZnAI204:Mn and i000 nm in AI203:Mn for T down to liquid helium temperature. It is argued that both a strong crystal field and a large Jahn-Teller splitting quench the luminescence of trivalent manganese and these results lower the benefits for using this ion in glasses.