Gem-quality elbaite from Paraíba, Brazil, containing up to 1.4 wt% Cu has been characterized using optical spectroscopy and crystal chemistry. The optical absorption spectra of Cu2+ in these tourmalines consist of two bands with maxima in the 695- to 940-nm region that are more intense in the Ec direction. The vivid yellowish green to blue-green colors of these elbaite samples arise primarily from Cu2+ and are modified to violet-blue and violet hues by increasing absorptions from Mn3+.

This content is PDF only. Please click on the PDF icon to access.

First Page Preview

First page PDF preview
You do not have access to this content, please speak to your institutional administrator if you feel you should have access.