Cornubite crystals from the Majuba Hill, Nevada, USA, Gerd Tremmel collection – small cabinet specimen as unique piece
This small cabinet specimen features intensely green Cornubite crystals on brown to greenish matrix. The crystals form dense, fine- to small-crystalline coatings and radial aggregates that clearly stand out from the surrounding host rock. The vivid emerald-green coloration creates a strong contrast with the ochre and rusty areas of the matrix. The crystals are clearly recognizable and dominate the overall appearance of the specimen.
The varied texture with alternating green tones, lighter mineral coatings and darker zones gives the piece a lively and natural character. As a classic secondary mineral from a well-known US locality, this small cabinet specimen combines aesthetic appeal with mineralogical interest.
Geology & Origin
Cornubite is a rare copper arsenate with the formula Cu₅(AsO₄)₂(OH)₄. It forms as a secondary mineral in the oxidation zone of copper-rich ore deposits through the weathering of primary sulfides. Majuba Hill in Nevada is a historically significant copper deposit known for a wide range of rare secondary copper minerals. Within these oxidized zones, arsenates such as Cornubite crystallized under suitable geochemical conditions in their characteristic green, fine-crystalline aggregates.
Legal Notice
Cinnabar contains mercury. This mineral is intended solely as a collector specimen. Avoid dust formation. Not suitable for children. Not intended for use in water or for experimental purposes.