Two pieces of Topaz was used for Raman spectra recording. The slightly colored crystal marked 1 and a cut rounded pebble marked 2.

The spectra of both crystals look quite similar except that the prismatic crystal has two additional bands at 1080 cm^-1 and 1170 cm^-1 . These two bands are generally absent from spectra taken at 532 or 785 nm. In the paper of Kloprogge and Frost about topaz from south Norway, these two peaks also appeared but the authors were also using a helium neon laser to excite Raman. It is believed that the two bands are not coming from vibrations but from fluorescence of chromium III ions. The same situation is observed with Beryl.

J.T.Kloprogge and R.L.Frost, Spectrochimica Acta part A 56, 2000, 501-513

Spectra of the OH stretching vibrations of Topaz strongly dependant on crystal orientation.