Ashoverite

Ashoverite
General
Category	Mineral
Formula (repeating unit)	Zn(OH)2
IMA symbol	Aov
Strunz classification	4.FA.10
Dana classification	6.2.11.1
Crystal system	Tetragonal
Identification
Color	Colourless, milky
Cleavage	Perfect on {001}
Luster	Vitreous, Dull
Streak	White
Diaphaneity	Translucent
Specific gravity	3.3
Optical properties	Uniaxial (+)

Ashoverite is one of three polymorphs of zinc hydroxide, Zn(OH)₂. It is a rare mineral first found in a limestone quarry near Ashover, Derbyshire, England, in 1988.^[1] It has also been found in the Harz mountain range in Germany, and in Namibia.

The mineral was discovered after samples of the polymorph sweetite were sent to labs by S. A. Rust. Some specimens contained what appeared to be baryte but, which on further examination, were found to be a previously undescribed mineral.

References

1. Clark, A. M.; Fejer, E. F.; Creesy, G; Tandy, P. C. (1988). "Ashoverite, a new mineral, and other polymorphs of Zn(OH)₂ from Milltown, Ashover, Derbyshire" (PDF). Mineralogical Magazine. 52 (368): 699–702. Bibcode:1988MinM...52..699C. doi:10.1180/minmag.1988.052.368.14.

• Handbook of Mineralogy
• Ashoverite Mineral Data, webmineral.com
• Mindat.org