Weight : 2.06 Carats. Dimension : 7 X 7 X 5.5 MM Color: Blue Green ( Deep Green ) Clarity : Loupe Clean Luster: Vitreous Associated month: October Crystal system: Hexagonal crystal system Hardness (Mohs hardness scale): 7 – 7.5 Transparency: Opaque, Transparent Refractive index: 1.616 – 1.65 Description: Tourmaline is the newer October birthstone. The name comes from the Sinhalese word toramalli, which means “stone with mixed colors,” because it often has multiple colors in one crystal…