Rhodizite

Irradiation of colorless stone produces intense yellow-(greenish): irradiated and natural color fade on long exposure to sunlight - Blue Chart Gem Identification, Herve Nicolas Lazzarelli, 2010, p 3 8 to 8.5Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references 3.34 to 3.44Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references DistinctArthur Thomas, Gemstones (2009) ConchoidalArthur Thomas, Gemstones (2009) 1.684 to 1.694Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references IsotropicHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) Anomalous double refractionMore from other references AnomalousMichael O?Donoghue, Gems, Sixth Edition (2006) Frequently displays anomalous birefringence NilArthur Thomas, Gemstones (2009) Colourless, pink, red, yellow-greenUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references TransparentUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references Adamantine,VitreousArthur Thomas, Gemstones (2009) Yellowish to greenishUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) Weak to moderate yellow-greenHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references Some specimens give a strong greenish or yellowish response with some phosphorescenceMichael O?Donoghue, Gems, Sixth Edition (2006) IsometricHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references Dodecahedra and tetrahedraMichael O?Donoghue, Gems, Sixth Edition (2006) More from other references Rhodizite occurs as a late-stage accessory mineral in alkali-rich granite pegmatites.Michael O?Donoghue, Gems, Sixth Edition (2006) "Fingerprints", thin needles, growth zoning - Blue Chart Gem Identification, Herve Nicolas Lazzarelli, 2010, p 3 Rhodizite information at mindat.org Madagascar  Gems, Sixth Edition, Michael O’Donoghue, 2006, p. 443 Behier, J. (1963): Carte mineralogique de Madagascar. Archive Service Géologique Madagascar. A 1871; [Eur.J.Min 13:159-165]; Russia  Gems, Sixth Edition, Michael O’Donoghue, 2006, p. 443 Gems, Sixth Edition, Michael O’Donoghue, 2006, p. 443