Sternbergite is a very rare silver iron sulphide that very rarely forms discernible crystals. It was first described in 1827, from Jáchymov, Karlovy Vary District in the northwest part of the Czech Republic bordering Germany. This rich large miniature specimen is from the famous silver mining region of Freiberg in Erzgebirge, Saxony, Germany but the wider orefield is somewhat similar mineralogically to Jáchymov. Specimens of Sternbergite from Jáchymov are very rare but from Freiberg even more so. On this specimen the Sternbergite forms dark, almost black, bladed microcrystals covering an area 2.5 x 1.5 cm in extent on Calcite. Undoubtedly very old, this specimen formed part of the exceptional systematic species collection assembled by brothers Martin and Michael Günther (1951-2007 & 1956-2021). Prior to that it was owned by Jeffries Rukin Jelks (1927-2014) and Herb Obodda (1942-) and is accompanied by both of their labels.
