GRR 313 image, 5K; Nearly colorless beryl from Minas Gerais, Brazil, 0.50 mm thick, looking down the c-axis. The figure compares spectra obtained in unpolarized light propagating down the c-axis before and after the crystal was heated to 1000°C. It is interesting to note that even at this high temperature, all the water is not lost. Data Files: unheated 23K; heated 23K.
Comparison, 5K; Comparison of the beryl spectra of GRR 313 and BW 1 in the 3800 cm-1 region. The bands in this region are from water in the channels. Both samples are plotted for 0.5 mm thickness of a (0001) slab in unpolarized radiation.
The band in the OH region are temperature dependent. Here are
the E||c and E
perp c spectra at room and liquid nitrogen temperature for a 1.067
mm thick slab of colorless beryl from Hunza, Paraiso, Pakistan.