Danburite

A pink color has been noted to form on irradiation (C.L. Key, unpublished observation). One would expect this to bleach on being heated; fading in light is also a possibility - Nassau (1984) 7Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references 2.97 to 3.03Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references ImperfectWalter Schumann, Gemstones of the world (2001) More from other references Uneven,ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references 1.627 to 1.639Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references Biaxial/+,-Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references 0.006Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references Weak: pale yellow - yellowHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references 0.017Arthur Thomas, Gemstones (2009) Yellow, yellow-brown, brown, pink, colourlessUlrich 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 VitreousArthur Thomas, Gemstones (2009) Weaker than LWHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) Inert to bright blue or blue-greenHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references RedMichael O?Donoghue, Gems, Sixth Edition (2006) OrthorhombicHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references Prismatic with rhombohedral to square cross-sectionMichael O?Donoghue, Gems, Sixth Edition (2006) More from other references Danburite occurs in granites and in metamorphosed carbonate rocks associated with hydrothermal activityMichael O?Donoghue, Gems, Sixth Edition (2006) "Fingerprints", parallel growth tubes (may create chatoyancy) - Blue Chart Gem Identification, Herve Nicolas Lazzarelli, 2010, p 4 Danburite information at mindat.org Japan  Gemstones, Arthur Thomas, 2009, p.116 Gems, Sixth Edition, Michael O’Donoghue, 2006, p. 403 Madagascar  Mexico  Gemstones, Arthur Thomas, 2009, p.116 Myanmar  Ted Themelis (2008) Gems & mines of Mogok Ted Themelis (2008) Gems & mines of Mogok Ted Themelis (2008) Gems & mines of Mogok Ted Themelis (2008) Gems & mines of Mogok Ted Themelis (2008) Gems & mines of Mogok Ted Themelis (2008) Gems & mines of Mogok Ted Themelis (2008) Gems & mines of Mogok Ted Themelis (2008) Gems & mines of Mogok Ted Themelis (2008) Gems & mines of Mogok Ted Themelis (2008) Gems & mines of Mogok Ted Themelis (2008) Gems & mines of Mogok Ted Themelis (2008) Gems & mines of Mogok USA