Zoisite Visible Spectra (400 - 1000 nm)

The blue variety, tanzanite, is colored by vanadium. It is highly pleochroic before it is heat-treated for the commercial gem market. Pink zoisite contains Mn3+. Green varieties contain Fe3+.

  Images of the zoisite absorption spectrum


    Pink Zoisite

    Green Zoisite

    Pale Yellow Zoisite

Faye GH and Nickel EH (1971) On the pleochroism of vanadium-bearing zoisite from Tanzania. Canadian Mineralogist  p812.

Langer K, Tillmanns E, Kersten M, Almen H, Arni RK (2002) The crystal chemistry of Mn3+ in the clino- and orthozoisite structure types, Ca2M33+[OH|O|SiO4|Si2O7]: A structural and spectroscopic study of some natural piemontites and “thulites” and their synthetic equivalents. Z Kristallogr 217:563-580

last  updated: 20-Dec-2014