Yellowish crystals of the rare arsenate mineral zykaite from the type locality: Kaňk, Kutná Hora (Kuttenberg), Bohemia, Czech Republic. — Photo: David Hospital · CC BY-SA 4.0
Zýkaite
Zýkaite is an IMA-recognized mineral species in the arsenate class, with the chemical formula Fe³⁺₄(AsO₄)₃(SO₄)(OH)·15H₂O.
It crystallizes in the orthorhombic crystal system.
Key properties: specific gravity 2.5; Pale yellowish streak; Dull luster; optically biaxial.
IMA symbol Zýk, IMA status: approved, named in 1976.
An alteration product of arsenopyrite and pyrite in ancient mine dumps.
It is found associated with Kaňkite, scorodite, pitticite, “limonite”, arsenopyrite, gypsum, quartz.
The mineral was named to honor Dr. Václav Zýka (1926–), Director, Institute of Raw Materials, Kutná Hora, Czech Republic.