Colour of Precious Opal

@article{Sanders1964ColourOP,
  title={Colour of Precious Opal},
  author={John V. Sanders},
  journal={Nature},
  year={1964},
  volume={204},
  pages={1151-1153}
}
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SINCE the work of Flörke1 it has generally been accepted that natural opaline silicas fall into two broad categories: (1) specimens which give X-ray patterns indicative of an obviously, although inExpand
Über Bragg‐Reflexe mit sichtbarem Licht an monodispersen Kunststofflatices. I
Mit Hilfe von Durchsicht- und Reflexionsspektren werden die Farberscheinungen an monodispersen Latices als Bragg-Reflexe mit sichtbarem Licht identifiziert. Durch eine vollstandige StrukturanalyseExpand
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SummaryA study of the optical behaviour of iridescent opal indicates very clearly that the silica present in the material has a regularly stratified structure in which the alternate layers differ inExpand
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Inhalt . Einleitung 183 1. Die homogenen Louchtkömer 184 2. Methodisches 185 3. Beschreibung der Erscheinung 187 4. Die verschiedenen Reflektogrammtypen 189 ö. Großzwillinge 196 6. Allgemeines zurExpand