True Blue

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True Blue beryl
Chemical composition Be3Al2(SiO3)6 Beryllium aluminum silicate
Crystal system Hexagonal
Habit Prismatic
Cleavage Poor, basal
Fracture Conchoidal to uneven
Hardness 7.5
Optic nature Uniaxial -
Refractive index 1.57 - 1.59
Birefringence 0.004 - 0,009
Dispersion Low, 0.014
Specific gravity 2.69
Lustre Vitreous
Pleochroism Distinct (shades of body color)

Discovered in the Yukon, Canada in 2004. An exceptionally dark blue aquamarine, whose color is the result of an extremely high concentration of iron. Unlike the Maxixe beryl, the color is photostable, which means that it is resistant to fading.

True Blue Beryl is a trade name for medium to dark blue aquamarine from Canada,marketed by True North Gems.

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