The Raman spectrum of smaragdite (2-6) is slightly different from those recorded on samples of actinolite (the same thing may be said about the Raman spectrum of the uralite sample, but this will be discussed separately). The wavenumbers and assignments of smaragdite and uralite samples (quartz included) are found in table (see above links of smaragdite and uralite) of smaragdite and uralite webpage in comparison with (2-2) actinolite, in order to emphasize small differences between them.

The intense band (ν₁) of the smaragdite spectrum corresponds to the symmetric stretching of Si-O_b-Si bridges at 670 cm^-1. The differences mentioned above consist in two regions with slightly moved peaks, as follows: in the region of asymmetric stretching of Si-O_b-Si (1000-1130 cm^-1), two peaks appear (1027 cm^-1 and 1052 cm^-1), the second peak being slightly shifted to the left in comparison with 2-2 (see Raman spectrum of actinolite and Raman spectrum of smaragdite); the second difference lies in the region of M-O vibrations, where the highest intensity peak is located at 389 cm^-1. The other peaks are very similar to peaks observed in actinolite samples (see table from actinolite webpage for the assignments of all peaks).

The Raman spectrum of uralite is a special case, as one band at 464 cm^-1 is from quartz. It should be noted that the sample of uralite contains some crystals of quartz, this being the reason of the presence of the 464 cm^-1 band. The spectrum of the quartz sample is labelled with 2-7b. As smaragdite spectrum, small differences appear in two regions, namely around 1010 cm^-1 and in M-O region (see below table). It should be pointed out that no Raman data have been found in the literature for these minerals species (smaragdite and uralite).

• The Mineralogy Database [link]

• Crystal data (.cif file) from the American Mineralogist Crystal Structure Database [link]

• ¹APOPEI A. I., BUZGAR N. (2010) - The Raman study of amphiboles. Anal. Şt. Univ. “Al. I. Cuza” Iaşi, Geologie, LVI/1 [link]