The Raman spectra of diamonds of the ultra-violet transparent type have been investigated using the 2536 resonance line of mercury as exciter. Besides the well-known 1332 Raman line, ten others with frequency shifts 1925, 2175·5, 2245, 2267, 2300·5, 2467, 2495, 2518, 2609·5 and 2664·6 cm.−1 have been recorded. These new lines have been identified as the octaves and allowed combinations of some of the eight fundamental frequencies of oscillation of the diamond structure of which the existence is indicated by the Raman theory of crystal dynamics, but which are not themselves permitted to appear in light-scattering by reason of the selection rules.