• DOI:10.1007/BF03172469
• Corpus ID: 128235557

The structure of labradorite and the origin of its iridescence

@article{Raman1950TheSO,
  title={The structure of labradorite and the origin of its iridescence},
  author={Chandrasekhara Venkata Sir Raman and A. Jayaraman},
  journal={Proceedings of the Indian Academy of Sciences - Section A},
  year={1950},
  volume={32},
  pages={1-16}
}

• C. Raman, A. Jayaraman
• Published 1 July 1950
• Geology
• Proceedings of the Indian Academy of Sciences - Section A

Labradorite which is a crystalline feldspar of the triclinic class is well known for the striking iridescence or play of colours which it exhibits. The phenomenon is displayed not only by specimens from the locality which gave its name to the substance, namely the coast of Labrador, but also by those from other parts of the world. This fact and the highly distinctive character of the effects observed suggest that they are in some way connected with the nature of the feldspar itself. Hintze (1897) reviewed the earlier attempts to find an explanation of the iridescence. Later investigations published about the same time by Rayleigh (1923) and by Boggild (1924) made useful contributions to the subject; but they left unanswered the fundamental questions which arise, namely, what is the material which is responsible for the iridescence of labradorite and why is it present? In the hope that a more searching examination of the phenomena than has hitherto been made might result in finding the answers to these questions, a representative collection of specimens was acquired for the crystallographic museum of this Institute. They have been carefully studied, and the investigation has revealed basic new facts concerning the iridescence of labradorite and enabled us to reach definite conclusions regarding its origin.