Cafarsite (rare)

Item Description

Cafarsite is a notably rare arsenate species, and the finest pieces are found at the famous mountain of Scherbadung (German name) or Cervandone (Italian name), in the Binntal on the Swiss/Italian border of the Alps. This mineral was named for its chemical composition (calcium, iron {Fe}, arsenate), but it turns out that the species has essential fluorine, so the chemical formula is going to be changed soon to reflect this. Additionally it appears that there is also sodium, manganese, aluminum and REE that will be part of the formula, as well. This is a good reference piece of Cafarsite from the type locality, featuring a bronze colored, altered dodecahedral crystals which are being replaced by a light green mineral what was originally said to be Mixite, but it seems it now identified as Agardite (specifically Agardite-(Y) in some cases) on matrix. The largest crystal measures about 3 mm across. A rather hard to find piece from this classic Alpine locality.
From the Alpine mineral collection of Richard ("Rich") Andrew Kosnar (1946-2007), the well-known mineral dealer and collector from Colorado, who was the namesake for the phosphate species Kosnarite. Rich loved European Alpine minerals, and he built a comprehensive suite of specimens from all the major localities.