Agate and chalcedony from igneous and sedimentary hosts aged from 13 to 3480 Ma: a cathodoluminescence study

  title={Agate and chalcedony from igneous and sedimentary hosts aged from 13 to 3480 Ma: a cathodoluminescence study},
  author={Terry Moxon and Stephen J. B. Reed},
  journal={Mineralogical Magazine},
  pages={485 - 498}
  • T. Moxon, S. Reed
  • Published 1 October 2006
  • Environmental Science
  • Mineralogical Magazine
Abstract Chalcedony and agates from a variety of world-wide hosts have been examined using cathodoluminescence (CL). Gaussian fitting of the experimental data shows that there are two dominant spectral emissions at ~400 and ~660 nm. A third subordinate peak is also found at ~470, ~560 or ~620 nm. An age-related link is shown between the respective decreasing and increasing relative intensities of the 660 and 620 nm emissions. It is proposed that this change is due to a condensation reaction… 
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