Hydrowoodwardite (Picture width: 5 mm) Locality: St. Briccius Mine, Königswalde at Annaberg, Erzgebirge, Saxony, Germany — Photo: Thomas Witzke · CC BY-SA 3.0 de
Hydrowoodwardite
Hydrowoodwardite is an IMA-recognized mineral species in the sulfate class, with the chemical formula (Cu₁₋ₓAlₓ)(SO₄)ₓ/₂(OH)₂·nH₂O (x 3x/2).
It crystallizes in the hexagonal crystal system (space group R-3m). It is a member of the Woodwardite, Hydrotalcite structural group.
Key properties: specific gravity 2.33; Pale blue streak; Vitreous luster.
IMA symbol Hwwd, IMA status: approved, named in 1996.
Rare in the oxidized portions of base metal sulfide mines.
It is found associated with Woodwardite, schulenbergite, namuwite, brianyoungite, langite, linarite, allophane, amorphous silica.
As the hydrated analog of woodwardite.