Spectra of chain silicates Pyroxene group

5 Spectra of chain silicates Pyroxene group 5.5.1 Background 

The pyroxene structure is also of considerable interest to mineral spectro-scopists because, like olivine, it again contains distinguishable coordination sites yielding distinctive Fe2+ crystal field spectra. In contrast to olivine, however, Fe2+ ions in pyroxenes show strong intracrystalline cation ordering, so that there are major compositional variations of visible to near-infrared spectra. 

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