GRCA_108407_ While Grand Canyon is most famous for vast views of towering cliffs, it holds additional geologic treasures, some as tiny as the delicate blue-green needles of a grandviewite crystal. Pete Berry and partners developed the Grandview Mine from two mining claims filed in 1890. The Grandview Trail was built in 1892-1893 to service the mine to haul ore out of the canyon by pack train. The ore consisted mostly of copper sulfate minerals including cyanotrichite, brochantite, and chalcoalumite, along with copper carbonates such as azurite and malachite. Like many historic mines in Grand Canyon, including the Orphan Mine, the mineralized zone is in a breccia pipe, which is a cylindrical mass of highly fractured rock. In the Grand Canyon region, breccia pipes formed from the collapse of solution caverns in the Redwall Limestone. The highly porous brecciated rock in these features was mineralized by copper- and/or uranium-bearing fluids. Learn more here: www.nps.gov/grca/naturescience/cynsk-v25.htm NPS photo by Michael Quinn — Photo: Public Domain · Public domain
Grandviewite
Grandviewite is an IMA-recognized mineral species in the sulfate class, with the chemical formula Cu₃Al₂(SO₄)(OH)₁₀·H₂O.
It crystallizes in the triclinic crystal system (space group P-1).
Key properties: Mohs hardness 2; specific gravity 2.81; Very pale blue streak; Vitreous luster; optically biaxial.
IMA symbol Gvw, IMA status: approved, named in 2007.
Forms secondarily through oxidation of Cu-bearing sulfides.
It is found associated with Chalcoalumite, cyanotrichite, carbonatecyanotrichite.
The name refers to the locality from which the first specimens were obtained.