This is an incredibly rare specimen of the species Spertiniite, named after the longtime chief mine geologist at this important industrial locality, Francesco Spertini. It came to me from his collection directly. The blue spots of rich spertiniite microcrystals are approx. 1 mm across. The piece has several groups of crystals, and they are eye visible. This specimen comes from the same pocket as the type specimen found in 1980 and was apparently the only pocket recovered. It is very expensive, because the owner sold it dearly... but it is also the only one I have seen on the market. Illustrated in the recent 2013 issue of Mineralogical Record devoted to this classic locale. Joe Budd photos.