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Published April 2001 | public
Journal Article

Fibrous nanoinclusions in massive rose quartz: The origin of rose coloration

Abstract

Pink nanofibers were extracted from rose quartz from 29 different pegmatitic and massive vein localities throughout the world. Their width varied from 0.1 to 0.5 μm. On the basis of optical absorption spectra of the fibers and the initial rose quartz, we conclude that these nanofibrous inclusions are the cause of coloration of massive rose quartz worldwide. These fibers do not occur in the rare, euhedral variety of pink quartz. Redox and heating experiments showed that the pink color of the fibers is due to Fe-Ti intervalence charge transfer that produces an optical absorption band at 500 nm. Based on the XRD patterns and characteristics of pleochroism, the best match for these inclusions is dumortierite. However, FTIR and Raman spectra consistently did not exactly match the standard dumortierite patterns, suggesting that this fibrous nanophase may not be dumortierite itself, but rather a closely related material.

Additional Information

© 2001 Mineralogical Society of America. Manuscript Received May 22, 2000; Manuscript Accepted December 7, 2000. Manuscript handled by Jeffrey E. Post. We thank the White Rose Foundation for their support of our research on color in minerals. We also thank John Brady, Milka de Brodtkorb, Rock H. Currier, Richard V. Gaines, George Harlow, Brian D. Hicks, Lothar Jung, Knut E. Larsen, Taijing Lu, Ole Peterson, Gunnar Raade, Ed Swoboda, Matt Taylor, and Jer Wednt for their interest in our work and for providing quartz samples. We also thank A.N. Platonov for multiple discussions regarding his work, and Liz Arredondo for assistance with laboratory measurements, George Harlow and an anonymous reviewer for valuable comments, and Jeffrey Post for the editorial review of the manuscript.

Additional details

Created:
August 22, 2023
Modified:
October 23, 2023