This crystal is an incredibly glassy Tanzanite, and for gemminess and luster it would certainly rank high on the charts. It has an uncommon, greenish-yellow color to it that is mesmerizing, with a glassiness that adds to the effect. So-called "Yellow Tanzanite" of this quality is quite rare. At 15.88 grams and about an inch in size, it is a perfect thumbnail. Complete (save for the base, of course) and pristine all around, it is even better in person.