Single-crystal X-ray and Raman investigation on melanophlogite from Varano Marchesi (Parma, Italy)

  title={Single-crystal X-ray and Raman investigation on melanophlogite from Varano Marchesi (Parma, Italy)},
  author={Mario Tribaudino and Andrea Artoni and Christian Mavris and Danilo Bersani and Pier Paolo Lottici and Daniele Belletti},
  journal={American Mineralogist},
  pages={88 - 94}
Abstract The results of a new single-crystal structure refinement and of a Raman spectroscopy investigation on melanophlogite, a clathrate structure of SiO2, are reported. The studied sample comes from a new finding at Varano Marchesi (Parma, Italy), and occurs in small veins and pockets along fractures in a siliceous marl from a chaotic complex. Melanophlogite is invariably separated from the host rock by a thin crust of opal-CT. Raman spectroscopy was done to investigate the guest molecules… 

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