Application of Raman Spectroscopy to Distinguish Metamorphic and Igneous Zircons

ABSTRACT

Raman spectroscopy is used for the first time for distinguishing igneous zircons from metamorphic zircons. Igneous zircons, especially those from granitic rocks, commonly show a Raman peak at 1461 Δcm⁻¹ with significant intensity, whereas metamorphic zircons do not show this peak or the peak is very weak. This may be related to the rare‐earth element (REE) contents in zircon. Thus, Raman spectroscopy provides a new, fast and non‐destructive means for investigating the structure and origin of zircons.

Keywords:

• Raman microspectrometry
• Zircon genesis
• Igneous zircons
• Metamorphic zircons
• Rare‐earth element

ACKNOWLEDGMENTS

This project was supported by a young outstanding researcher award to M. Sun from HKU and a research grant from the Faculty of Science, The University of Hong Kong. We are grateful to Professor Simon Wilde for inspiring discussion. We thank our colleagues Dr. Y. L. Sun, Miss Y. Luo, and Mr. X. P. Xia for their useful input. We also thank Miss Y. F. Poon in the Department of Botany and Dr. K. H. Leung in the Department of Chemistry for assistance in the analysis of the Raman data. A HKU postgraduate studentship to the first author is greatly acknowledged.

Notes

^aPhotons per second for peak 1461 Δcm⁻¹.