Indicolite tourmaline is a rare and highly prized blue variety of the complex elbaite tourmaline mineral family. Derived from the Latin word indicum, meaning indigo, it stands out as one of the rarest and most collectible color variations of tourmaline… Color Range: It occurs in shades of light sky blue, deep indigo, violet-blue, and teal or greenish-blue. The blue hue is caused by trace amounts of iron and titanium impurities trapped inside the crystal structure… Indicolite is strongly pleochroic, meaning it displays different shades or intensities of blue and green depending on the angle from which it is viewed… From Afghanistan Weight : 25 grams