Optical absorption and electron spin resonance in blue and green natural beryl: A reply

@article{Blak1982OpticalAA,
  title={Optical absorption and electron spin resonance in blue and green natural beryl: A reply},
  author={Ana Regina Blak and Sadao Isotani and Shigueo Watanabe},
  journal={Physics and Chemistry of Minerals},
  year={1982},
  volume={9},
  pages={279-280}
}
A comparative study of blue and green beryl crystals (from the region of Governador Valadares, Minas Gerais, Brazil) using electron paramagnetic resonance (EPR) and optical absorption (OA) spectroscopy is reported. The EPR spectra show that Fe3+ in blue beryl occupies a substitutional Al3+ site and in green beryl is localized in the structural channels between two O6 planes. On the other hand the infrared spectra show that the alkali content in the blue beryl is mostly at substitutional and/or… 

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