7.45 Carat Tanzanite and Diamond Cocktail Ring.  The lush blue Tanzanite is a relatively recent discovery and is found in only one place on earth, near the remote area of Mount Kilimanjaro. This striking 7.45 carat center stone is encircled by a halo of 2.12 carats of round brilliant diamonds and uniquely placed marquise shapes on the sides. Set in 18 karat white gold.