Kambaldaite, NaNi₄(CO₃)₃(OH)₃·3H₂O, is an extremely rare hydrated

sodium Sodium is a chemical element; it has Symbol (chemistry), symbol Na (from Neo-Latin ) and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 element, group 1 of the peri ...

nickel Nickel is a chemical element; it has symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive, but large pieces are slo ...

carbonate mineral Carbonate minerals are those minerals containing the carbonate ion, . Carbonate divisions Anhydrous carbonates *Calcite group: trigonal **Calcite CaCO3 **Gaspéite (Ni,Mg,Fe2+)CO3 **Magnesite MgCO3 **Otavite CdCO3 **Rhodochrosite MnCO3 **Sider ...

described from

gossan Gossan (eiserner hut or eisenhut) is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein. In the ''classic'' gossan or iron cap all that remains is iron oxides and quartz, often ...

iferous material associated with

Kambalda type komatiitic nickel ore deposits Kambalda type komatiitic nickel ore deposits are a class of magmatic iron-nickel-copper-platinum-group element ore deposit in which the physical processes of komatiite volcanology serve to deposit, concentrate and enrich a Fe-Ni-Cu-(PGE) sulfide ...

at Kambalda, Western Australia, and Widgie Townsite nickel gossan, Widgiemooltha,

Western Australia Western Australia (WA) is the westernmost state of Australia. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to the south, the Northern Territory to the north-east, and South Australia to the south-east. Western Aust ...

. Kambaldaite crystallizes in the hexagonal system, is light green to blue, and forms drusy to mammilla encrustations on the matrix. Kambaldaite was first described in 1985 from the gossan of the Otter Shoot nickel orebody, Kambalda, during mining of the gossans material. Kambaldaite, though in lesser and rarer amount, is also found in the Widgiemooltha nickel gossans, probably discovered there in the early to mid-1990s.

Paragenesis

Kambaldaite is formed in the

regolith Regolith () is a blanket of unconsolidated, loose, heterogeneous superficial deposits covering solid rock. It includes dust, broken rocks, and other related materials and is present on Earth, the Moon, Mars, some asteroids, and other terrestria ...

as a supergene alteration mineral of nickel sulfide minerals, in arid or semi-arid environments which produce conditions amenable to a concentration of calcareous or carbonate minerals in the weathering profile. Kambaldaite from Kambalda and Widgiemooltha is associated with komatiite-associated nickel sulfide gossans and is probably formed by substitution of nickel into carbonates such as

magnesite Magnesite is a mineral with the chemical formula ( magnesium carbonate). Iron, manganese, cobalt, and nickel may occur as admixtures, but only in small amounts. Occurrence Magnesite occurs as veins in and an alteration product of ultramafic r ...

which are formed by oxidation of the lithology, and oxidation of primary and supergene nickel sulfide minerals. Kambaldaite is formed from a similar process to the weathering of other sulfide minerals to form carbonate minerals. The sulfide minerals which are weathered to produce kambaldaite are

pentlandite Pentlandite is an iron–nickel sulfide with the chemical formula . Pentlandite has a narrow variation range in nickel to iron ratios (Ni:Fe), but it is usually described as 1:1. In some cases, this ratio is skewed by the presence of pyrrhotite ...

, violarite, millerite and rarely

nickeline Nickeline or niccolite is the mineral form of nickel arsenide. The naturally-occurring mineral contains roughly 43.9% nickel and 56.1% arsenic by mass, but composition of the mineral may vary slightly. Small quantities of sulfur, iron and cobalt ...

Occurrence

Kambaldaite is associated with

goethite Goethite (, ) is a mineral of the diaspore group, consisting of iron(III) oxide-hydroxide, specifically the α- polymorph. It is found in soil and other low-temperature environments such as sediment. Goethite has been well known since ancient t ...

malachite Malachite () is a copper Carbonate mineral, carbonate hydroxide mineral, with the chemical formula, formula Basic copper carbonate, Cu2CO3(OH)2. This opaque, green-banded mineral crystallizes in the monoclinic crystal system, and most often for ...

annabergite 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 kn ...

, gaspeite and

in the nickel sulfide gossans of Kambalda and Widgiemooltha. It is not known from other nickel sulfide gossans within the Yilgarn craton, potentially due to many of these existing within areas of

laterite Laterite is a soil type rich in iron and aluminium and is commonly considered to have formed in hot and wet tropical areas. Nearly all laterites are of rusty-red coloration, because of high iron oxide content. They develop by intensive and prolo ...

cover, deeper

development, or less favorable rainfall conditions. Kambaldaite has not reported from the

Tasmania Tasmania (; palawa kani: ''Lutruwita'') is an island States and territories of Australia, state of Australia. It is located to the south of the Mainland Australia, Australian mainland, and is separated from it by the Bass Strait. The sta ...

n or

New South Wales New South Wales (commonly abbreviated as NSW) is a States and territories of Australia, state on the Eastern states of Australia, east coast of :Australia. It borders Queensland to the north, Victoria (state), Victoria to the south, and South ...

nickel carbonate occurrences because it is a supergene carbonate mineral and not a

hydrothermal Hydrothermal circulation in its most general sense is the circulation of hot water (Ancient Greek ὕδωρ, ''water'',Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir Henry Stuart Jones. with th ...

mineral. Kambaldaite is also reported from the Inn valley, North Tyrol,

Austria Austria, formally the Republic of Austria, is a landlocked country in Central Europe, lying in the Eastern Alps. It is a federation of nine Federal states of Austria, states, of which the capital Vienna is the List of largest cities in Aust ...

, and from Linopolis,

Minas Gerais Minas Gerais () is one of the 27 federative units of Brazil, being the fourth largest state by area and the second largest in number of inhabitants with a population of 20,539,989 according to the 2022 Brazilian census, 2022 census. Located in ...

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

References

* * Thornber, M. R. (1972) ''Pyrrhotite-the matrix of nickel sulfide mineralization.'' Newcastle Conference, Australasian Institute of Mining and Metallurgy, May-June, 1972, 51-58. * Thornber, M. R. (1975a) ''Supergene alteration of sulfides, I. A chemical model based on massive nickel sulfide deposits at Kambalda, Western Australia.'' Chemical Geology, 15, 1-14. * Thornber, M. R. (1975b) ''Supergene alteration of sulfides, II. A chemical study of the Kambalda nickel deposits.'' Chemical Geology, 151 117-144. *
Kambaldaite on Mindat.org
{{carbonate-mineral-stub Nickel minerals Carbonate minerals Sodium minerals Hexagonal minerals Minerals in space group 173 Nickel mining in Western Australia

Paragenesis

Occurrence

See also

References