Stibioclaudetite is a very rare zinc arsenate, and to find a well-developed cluster like this is even more rare. The crystals are gemmy and glassy, as good as you will find for sheer quality. Tsumeb is the Type Locality, with the species being named for a single specimen found in 1977. In all the previous years at Tsumeb, none had been found until the miners went down to a third oxidation zone and encountered a bizarre, germanium-rich zone from which new species came in profusion. This specimen is from the Zinc Pocket on the 44th level, one of the deepest parts of the mine. Leiteite and Ludlockite are among the most well known of these Type Locality rarities. This came from a later pocket after the first find, and was unique in the sharp, gemmy crystals from this small pocket - and remains so, to this day. It is an IMPORTANT specimen and crystal for a very interesting species that also happens to be a competitive level thumbnail specimen. Ex. Mark Rattay and Marshall Sussman (from his important rarities suite, sold off in 2003 to me). Much better in person. In 25 years of being a dealer at a level enough to notice, I have seen only three crystals for sale from this pocket.