Ball-and-stick model of the unit cell of the mineral kernowite , Cu 2 Fe(AsO 4 )(OH) 4 ·4(H 2 O), based on the crystal structure of the isostructural mineral liroconite . The structure of liroconite was determined by single-crystal X-ray diffraction and reported in Acta Cryst. C (1991) 47 , 916-919 ( COD entry 9007883 , AMCSD entry 11889 ). Colour code: Copper, Cu: orange-brown Iron, Fe: blue-grey Arsenic, As: lilac Oxygen, O: red Water, H 2 O: pale green Model manipulated and image generated in CCDC Mercury 3.8 . — Photo: Ben Mills · Public domain
Kernowite
A copper-iron arsenate described in 2020 — a liroconite-group mineral named Kernow, the Cornish word for Cornwall.
Intro adapted from Wikipedia (CC BY-SA).
Kernowite is an IMA-recognized mineral species in the arsenate class, with the chemical formula Cu₂Fe³⁺(AsO₄)(OH)₄·4H₂O.
It crystallizes in the monoclinic crystal system (space group I2/a). It is a member of the Liroconite structural group.
Key properties: specific gravity 3.048.
IMA symbol Knw, IMA status: approved, named in 2020.
Secondary in cavities in quartz-gossan, rich in undifferentiated micro-crystalline gray sulfides. Perhaps related closely to the formation of arsenic-rich gels/mineraloids.
It is found associated with Liroconite, poorly crystalline arsenic phases including pharmacosiderite and olivenite- group minerals.
The name commemorates the world for Cornwall in the Cornish language (Kernow). The Fe3+-analogue of liroconite.