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New Gem Mineral Species Pezzottaite: Physical and Optical Properties

		*Fig. P12* Natural cat's eye pezzottaite Cutting of pezzottaite as a cabochon intersecting the direction of the growth tubes produces a so-called cat's eye effect (see white line produced by a directed light source perpendicular to the direction of the c-axis)
*Fig. P13* Pezzottaite rough of 29.41 ct (see also Fig.P5) is shown as seen through crossed polarizers. A projection sphere is introduced to show the uniaxial property of "pezzottaite" (Cross pattern if viewd in the direction of the c-axis)

BOX 3 PHYSICAL AND OPTICAL PROPERTIES (IMA)

Fig. P14a : Polarized UV-VIS-NIR spectra on a 6mm thick slice of pezzottaite which was used for chemical and crystal structure analysis. Note: Absorption bands at 494 and 563 (polarized perpendicular to the c-axis) and 572 nm (polarized parallel to the c-axis)

Fig. P14b : Pleochroism of pezzottaite with orange-red to purple is shown which is distinctively different from other minerals of the beryl group, such as pink beryl "morganite" (see Laurs et al., 2003)