13.78ct Unheated Raw Tanzanite Crystal

This natural unheated tanzanite crystal is almost a bicolor, as towards the termination there is much richer violet/blue color than the base of the crystal.  You can see the zoning clearly and it has a very neat look! This crystal weighs 13.78 carats and measures 18.9mm x 10.8mm x 7.7mm. This crystal is unheated and shows the trichroic colors in the dichroscope.