Ninety oval mixed cut natural tanzanites, measuring 4.00 x 3.00 x 1.95mm, exact total weight 16.46ct., clarity is eye clean, type I, medium dark, very slightly grayish, bluish violet color, (GIA bV 6/3), cut is good. Transmitting light with no distortion, transparent. Color grade is an average for the group. Graded in the setting. Tanzanite is a very rare gemstone that is only found in the country of Tanzania. Originally discovered in 1967. Tiffany & Company, named the stone Tanzanite. It is found in the Usumburu Mountains that border the Umba Valley of northern Tanzania. Tanzanite occurs in gray, brown, violet, blue, reddish-purple, & green. The gem is interesting because of its exceptional pleochroism. Rotated in different directions a tanzanite will exhibit multiple changes of color. Tanzanite has a low tolerance to ultrasonic cleaning, and should not be cleaned using this method. Westfield Appraised at $1,585.00.