Annabergite

  Annabergite is a mineral consisting of a hydrous nickel arsenate, Ni₃(AsO₄)₂·8H₂O, crystallizing in the monoclinic system and isomorphous with vivianite and erythrite. Crystals are minute and capillary and rarely met with, the mineral occurring usually as soft earthy masses and encrustations. A fine apple-green colour is its characteristic feature. It was long known (since 1758) under the name nickel ochre; the name annabergite was proposed by H. J. Brooke and W H. Miller in 1852, from Annaberg in Saxony, one of the localities of the mineral. It occurs with ores of nickel, of which it is a product of alteration. A variety, from Creetown in Kirkcudbrightshire, in which a portion of the nickel is replaced by calcium, has been called dudgeonite, after P. Dudgeon, who found it.

Additional recommended knowledge

Better weighing performance in 6 easy steps

How to ensure accurate weighing results every day?

Recognize and detect the effects of electrostatic charges on your balance

Closely related is cabrerite wherein some of the nickel is replaced by magnesium. It is named for Sierra Cabrera in Spain where it was originally found.

References

• This article incorporates text from the Encyclopædia Britannica Eleventh Edition, a publication now in the public domain.