Willemite is rare in finely crystallized specimens and there are only a few localities in the world that produce great display specimens, Tsumeb among them. This small cabinet specimen appears to have two generations of Willemite. The first generation consists of gemmy, thin prisms that make thin clusters with white cores. These are up to 3 mm in size, and they fluoresce white. The second generation is more classic, but rare. The Willemite is in lustrous, spherical, green-blue color, crystal aggregates. These are about 7 mm across, forming a layer that covers half the presentation side. These have a blue fluorescence. The Willemite specimens from Tsumeb are highly prized for their wide range of colors and attractiveness. I am told that this style came out in the 1970s. Certainly, few enough are ever on the market and they are, to me, world's best of species for sheer beauty. This piece particularly has amazing wet luster!