This is a very beautiful, very clean 4.55ct cushion cut tanzanite. This stone would make an elegant ring or center stone for a pendant. It's color, cut and clarity makes this an exceptional stone.
Tanzanite is the blue variety of the mineral Zoisite, found the Merelani Hills near Arusha, Tanzania. Gem quality tanzanite has only been found in this remote location of East Africa. Tanzanite is a trichroic gemstone, meaning that it shows three colors down its different axis, making orienting the rough before cutting very important. Like tsavorite, tanzanite is a newly discovered gemstone, first found in the 1960s. Tiffany & Company recognized that this amazing blue stone would become an international seller and quickly became its main distributor. Tanzanites popularity has grown steadily ever since. Many Tanzanites are heat treated to produce colors ranging from a soft pale blue through to vibrant dark violetish blue and even blueish purple. Rich, deep hues are the most valued but it is rare to find those colors in stones less than 4cts.