Elpasolite , Chiolite (Dimensions: 1 cm x 1 cm x 0.5 cm) Locality: Morefield Mine (Morefield pegmatite), Winterham, Amelia Co., Virginia, USA Original description: Purple sugary elpasolite xls. forming small trapezohedrons intermix with chiolite xls. from a cavity in the cryolite. 10/10/2003 alumino-fluoride pocket 45’ level 230’ NE floor. Photographer Shaun Mackey. Collector & owner Mark Wylie — Photo: Mark Joseph Wylie · Public domain
Elpasolite
Elpasolite is an IMA-recognized mineral species in the halide class, with the chemical formula K₂NaAlF₆.
It crystallizes in the cubic crystal system (space group Pa3). It is a member of the Perovskite structural group.
Key properties: Mohs hardness 2.5; specific gravity 2.98; Weakly vitreous to slightly greasy luster.
IMA symbol Elp, grandfathered status — known before the IMA’s founding, named in 1883.
Replacing fluorine-bearing minerals in a quartz-microcline pegmatite (Pikes Peak, Colorado, USA); on vein quartz in a hydrothermal antimony deposit in silicified limestone (Cetine mine, Italy).
It is found associated with Cryolite, pachnolite, thomsenolite, prosopite, gearksutite (Pikes Peak, Colorado, USA); cryolite, chiolite, pachnolite, thomsenolite, ralstonite (Amelia.
The name refers to El Paso County, Colorado, USA, where the mineral was found.