Annabergite is an arsenate mineral consisting of a hydrous nickel arsenate. It is considered a member of the vivianite group and known for its ability to form crystals in a characteristic apple-green color.
History
Annabergite has been known since the 18th century, although type localities were not published along initial descriptions. The first report of Annabergite by Axel Fredrik Cronstedt from 1758 erroneously identifies it as a nickel oxide mineral and assigned it the latinized name Ochra niccoli, while Wallerius gave it the name nickel bloom in 1778.
Annabergite was thoroughly described in 1852 by Brooke and Miller
Calcium-bearing specimens, known from Creetown in Kirkcudbrightshire, have been called Dudgeonite, named after its discoverer P. Dudgeon.