Morganite

From The Gemology Project
Revision as of 13:31, 2 October 2006 by Barbra (talk | contribs)
Jump to: navigation, search
Morganite
Chemical composition Be3Al2(SiO3)6 Beryllium aluminium silicate
Crystal system Hexagonal
Habit Prismatic
Cleavage Poor, basal
Fracture Conchoidal to uneven
Hardness 7.5
Optic nature Unixaial -
Refractive index 1.58 - 1.60
Birefringence 0.008 - 0.009
Dispersion Low, 0.014
Specific gravity 2.80 - 2.90
Lustre Vitreous
Pleochroism Weak to moderate (shades of body color)

Morganite is the pink, peach or lilac variety of the mineral beryl. It is a beryllium aluminum silicate colored with a trace amount of manganese. The stone was named after the American banker and gem lover, J. P. Morgan, shortly after it was first discovered in 1902 in the Malagasy Republic (Madagascar). Fine examples are currently found in Minas Gerais, Brazil and Madagascar.