This flat presents a varied collection of Parnauite, Philipsbornite and other secondary copper and lead minerals from the well known Grandview Mine in the Grand Canyon, Arizona, USA. The specimens display mainly greenish blue, turquoise and yellowish green mineral coatings and crystalline aggregates on light brown to grey matrix. Several pieces show clearly recognizable crystal structures in the form of fine crusts and irregular crystal aggregates, while other specimens exhibit broader mineral surfaces with distinct color zoning. The combination of vivid colors and diverse textures gives the flat a visually rich and mineralogically diverse overall appearance.
Geology & Origin
The Grandview Mine is a classic locality for secondary phosphate, arsenate and sulfate minerals formed by the oxidation of primary copper and lead ores. Parnauite and Philipsbornite crystallize in the weathering zone under arid climatic conditions when copper and lead bearing solutions interact with phosphates and arsenates. Within fractures and cavities of the host rock, complex mineral parageneses develop that include numerous rare associated species. The locality is regarded worldwide as one of the most important sources for these rare secondary minerals and is especially known for characteristic micromount and small suite specimens.