Golden-orange Imperial Topaz from Ouro Preto is world renowned, not only for the intense and instantly recognizable color but also for the luster, gemminess, and form. Those Imperials that are pinkish-lavender, such as this fine thumbnail, are considerably less common and also highly prized. The prism faces are glassy, and the termination well-formed. There is some edgewear on a microscopic scale, but it does not detract at all from the fine aesthetics. I believe the Imperial Topaz that tend towards the purplish end of the spectrum were from a single-pocket discovery in the 1980's. A choice thumbnail, to be sure.