Brazil, Color: bi-color, violet / yellow, Hardness: 7, Refractive index: 1.54 1.55, Density: 2.65 2.66, Chemical composition: SiO2, Crystal structure: hexagonal, Lustre: vitreous, Origins: Brazil, Bolivia, Uruguay. Ametrine is a bi-color variety of quartz, Yellow, Orange, India
Ethiopia, Afghanistan, China, Australia, Color: light greenish blue, pale yellow or colorless. Hardness: 5.5 6, Refractive index: 1.58 1.61, Density: 3.04 3.11, Chemical composition: LiAl(PO4)F, Crystal structure: triclinic, Origins: Brazil (major source); also found in USA, Germany, France, UK, Finland, Norway, Sweden, Namibia, Zaire, China and Australia., Axinite is a collectors stone that is rarely used in jewelry.
Yellow
Brown, Green, White, Colorless, Yellow, Blue, gray, pink, Greenish
Not Available
Sub-Conchoidal, Irregular/uneven, Uneven, ConchoidalArthur Thomas, Gemstones (2009)
SiO2
(Li,Na)Al(PO 4)(F,OH)Michael OâDonoghue , Gems, Sixth edition (2006) More from other references