Vesignieite crystals from Andreasbachtal, Harz, Germany – cabinet specimen as unique piece
This cabinet specimen features Vesignieite in a light-colored quartz matrix from the well-known Andreasbachtal locality in the Harz Mountains. Green Vesignieite crystals and crystalline aggregates are visible across several areas of the specimen, providing subtle color contrasts against the predominantly pale matrix. The combination of this rare copper barium vanadate with the contrasting host rock gives the piece strong mineralogical appeal. The crystals occur mainly as small embedded groups but can be recognized clearly with magnification.
Geology & Origin
Vesignieite is a rare copper barium vanadate with the chemical formula BaCu₃(VO₄)₂(OH)₂. It forms within the oxidation zones of vanadium-bearing copper deposits and is known from only a limited number of localities worldwide. Andreasbachtal in the Harz Mountains is one of Germany's classic occurrences for rare secondary minerals. The Vesignieite found here developed through the alteration of primary copper minerals under oxidizing conditions and is highly appreciated by collectors because of its rarity.