This flat contains an extensive collection of Philipsbornite and Osarizawaite crystals from the famous Grandview Mine in the Grand Canyon, USA. The specimens display predominantly dense yellow to yellow green crystal aggregates, locally accompanied by green to blue green areas. The crystals are generally small but clearly recognizable as crystalline coatings and aggregates covering large parts of the matrix. The flat shows a wide range of color intensity, surface texture, and crystal development, adding significant scientific and collector value to the collection.
Geology & Origin
Philipsbornite and Osarizawaite are rare secondary lead copper arsenates that form in the oxidation zones of arsenic rich lead and copper deposits. The Grandview Mine in the Grand Canyon is internationally renowned for its exceptional diversity of secondary uranium and arsenate minerals. Both minerals form through the alteration of primary ore minerals under strongly oxidizing conditions and commonly occur as fine crystalline coatings on sandstone matrix. Specimens from this classic locality are highly sought after due to their rarity, vivid coloration, and historical significance.