Annabergite
Encyclopedia
Annabergite is an arsenate 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.
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.
Arsenate mineral
Arsenate minerals usually refer to the naturally occurring orthoarsenates, possessing the 3- anion group and, more rarely, other arsenates with anions like AsO32- or [AsO22]- . Arsenite minerals are much less common...
consisting of a hydrous nickel
Nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...
arsenate
Arsenate
The arsenate ion is AsO43−.An arsenate is any compound that contains this ion. Arsenates are salts or esters of arsenic acid.The arsenic atom in arsenate has a valency of 5 and is also known as pentavalent arsenic or As[V]....
, Ni3(AsO4)2·8H2O, crystallizing
Crystallization
Crystallization is the process of formation of solid crystals precipitating from a solution, melt or more rarely deposited directly from a gas. Crystallization is also a chemical solid–liquid separation technique, in which mass transfer of a solute from the liquid solution to a pure solid...
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
Annaberg-Buchholz
Annaberg-Buchholz is a town in the Free State of Saxony, Germany, in the Erzgebirge, capital of the district Erzgebirgskreis.The town is located in the Ore Mountains, at the side of the Pöhlberg . It has three Protestant churches, among them that of St...
in Saxony
Saxony
The Free State of Saxony is a landlocked state of Germany, contingent with Brandenburg, Saxony Anhalt, Thuringia, Bavaria, the Czech Republic and Poland. It is the tenth-largest German state in area, with of Germany's sixteen states....
, 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.
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.