Spectroscopy of a birefringent grossular from Asbestos, Quebec, Canada

George R. Rossman, Roger D. Aines
Division of Geological and Planetary Sciences
California Institute of Technology, Pasadena, CA  91125, USA


  The infrared spectra of birefringent garnets from Asbestos, Quebec, Canada, show strong anisotropy in the OH stretching region , but are devoid of anisotropy in the Fe2+ electronic bands and in the SiO4 overtone region. These results suggest that the birefringence arises from a noncubic orientation of the OH groups that are from a minor hydrogrossular component.