Gaspeite
Encyclopedia
Gaspeite is an extremely rare nickel
carbonate mineral named for the place it was first described, in the Gaspé Peninsula
, Canada
.
Gaspeite's formula is (Ni,Fe,Mg)CO3 and it is a bright green mineral. It forms massive to reniform pappillary aggregates in fractures, bottryoidal concretions in laterite
or fracture infill. It is also present as stains and patinas on iron oxide boxworks of gossan
ous material.
as a supergene
alteration mineral of nickel sulfide minerals, generally in arid or semi-arid environments which produce conditions amenable to concentration of calcareous or carbonate minerals in the weathering profile.
Gaspeite from Widgiemooltha is associated with talc carbonate
d komatiite
-associated nickel sulfide gossan
s and is probably formed by substitution of nickel into carbonates such as magnesite
which are formed by oxidation of the talc-carbonate lithology, and of primary and supergene nickel sulfide minerals.
Gaspeite 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 gaspeite are pentlandite
, violarite
, millerite
and rarely nickeline.
in Kambalda
, and nearby Widgie Townsite, Widgiemooltha, both south of Kalgoorlie, Western Australia, in both locations also associated with garnierite
and kambaldaite
.
Nickel carbonate, though not conclusively proven to be gaspeite, is also reported in hydrothermally altered ultramafic rocks in New South Wales, Australia, associated with serpentinite
bodies and lode gold deposits.
Gaspeite is reported from the Lord Brassey Mine, Tasmania, in association with hellyerite
.
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...
carbonate mineral named for the place it was first described, in the Gaspé Peninsula
Gaspé Peninsula
The Gaspésie , or Gaspé Peninsula or the Gaspé, is a peninsula along the south shore of the Saint Lawrence River in Quebec, Canada, extending into the Gulf of Saint Lawrence...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
.
Gaspeite's formula is (Ni,Fe,Mg)CO3 and it is a bright green mineral. It forms massive to reniform pappillary aggregates in fractures, bottryoidal concretions in laterite
Laterite
Laterites are soil types rich in iron and aluminium, formed in hot and wet tropical areas. Nearly all laterites are rusty-red because of iron oxides. They develop by intensive and long-lasting weathering of the underlying parent rock...
or fracture infill. It is also present as stains and patinas on iron oxide boxworks of gossan
Gossan
Gossan 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 in the form of boxworks, quartz lined cavities retaining the shape of the dissolved...
ous material.
Paragenesis
Gaspeite is formed in the regolithRegolith
Regolith is a layer of loose, heterogeneous material covering solid rock. It includes dust, soil, broken rock, and other related materials and is present on Earth, the Moon, some asteroids, and other terrestrial planets and moons.-Etymology:...
as a supergene
Supergene (geology)
In ore deposit geology, supergene processes or enrichment occur relatively near the surface. Supergene processes include the predominance of meteoric water circulation with concomitant oxidation and chemical weathering. The descending meteoric waters oxidize the primary sulfide ore minerals and...
alteration mineral of nickel sulfide minerals, generally in arid or semi-arid environments which produce conditions amenable to concentration of calcareous or carbonate minerals in the weathering profile.
Gaspeite from Widgiemooltha is associated with talc carbonate
Talc carbonate
Talc carbonate is a geologic term for a suite of rock and mineral compositions found in metamorphic ultramafic rocks.The term refers to the two most common end-member minerals found within ultramafic rocks which have undergone talc-carbonation or carbonation reactions, talc and the carbonate...
d komatiite
Komatiite
Komatiite is a type of ultramafic mantle-derived volcanic rock. Komatiites have low silicon, potassium and aluminium, and high to extremely high magnesium content...
-associated nickel sulfide gossan
Gossan
Gossan 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 in the form of boxworks, quartz lined cavities retaining the shape of the dissolved...
s and is probably formed by substitution of nickel into carbonates such as magnesite
Magnesite
Magnesite is magnesium carbonate, MgCO3. Iron substitutes for magnesium with a complete solution series with siderite, FeCO3. Calcium, manganese, cobalt, and nickel may also occur in small amounts...
which are formed by oxidation of the talc-carbonate lithology, and of primary and supergene nickel sulfide minerals.
Gaspeite is formed from a similar process to the weathering
Weathering
Weathering is the breaking down of rocks, soils and minerals as well as artificial materials through contact with the Earth's atmosphere, biota and waters...
of other sulfide minerals to form carbonate minerals. The sulfide minerals which are weathered to produce gaspeite are pentlandite
Pentlandite
Pentlandite is an iron-nickel sulfide, 9S8. Pentlandite usually has a Ni:Fe ratio of close to 1:1. It also contains minor cobalt.Pentlandite forms isometric crystals, but is normally found in massive granular aggregates. It is brittle with a hardness of 3.5 - 4 and specific gravity of 4.6 - 5.0 and...
, violarite
Violarite
Violarite is a supergene sulfide mineral associated with the weathering and oxidation of primary pentlandite nickel sulfide ore minerals....
, millerite
Millerite
Millerite is a nickel sulfide mineral, NiS. It is brassy in colour and has an acicular habit, often forming radiating masses and furry aggregates...
and rarely nickeline.
Occurrence
Gaspeite is known from a handful of locations worldwide. Aside from its type locality in Canada, gaspeite is found in the nickeliferous gossans of Kambalda type komatiitic nickel ore depositsKambalda type komatiitic nickel ore deposits
Kambalda type nickel ore deposits are a class of magmatic nickel-copper ore deposit in which the physical processes of komatiite volcanology serve to enrich, concentrate and deposit nickel-bearing sulfide within the lava flow environment of an erupting komatiite volcano.-Classification:The...
in Kambalda
Kambalda, Western Australia
Kambalda is a small mining town about 60 kilometres from the mining city of Kalgoorlie in Western Australia, within the Goldfields. It is split into two townsites 4 kilometres apart, Kambalda East and Kambalda West; and is located on the western edge of a giant salt lake, Lake Lefroy...
, and nearby Widgie Townsite, Widgiemooltha, both south of Kalgoorlie, Western Australia, in both locations also associated with garnierite
Garnierite
Garnierite is a general name for a green nickel ore which is found in pockets and veins within weathered and serpentinized ultramafic rocks. It forms by lateritic weathering of ultramafic rocks and occurs in many nickel laterite deposits in the world. It is an important nickel ore, having a large...
and kambaldaite
Kambaldaite
Kambaldaite, NaNi433·3H2O, is an extremely rare hydrated sodium nickel carbonate mineral described from gossanous material associated with Kambalda type komatiitic nickel ore deposits at Kambalda, Western Australia, and Widgie Townsite nickel gossan, Widgiemooltha, Western Australia.Kambaldaite...
.
Nickel carbonate, though not conclusively proven to be gaspeite, is also reported in hydrothermally altered ultramafic rocks in New South Wales, Australia, associated with serpentinite
Serpentinite
Serpentinite is a rock composed of one or more serpentine group minerals. Minerals in this group are formed by serpentinization, a hydration and metamorphic transformation of ultramafic rock from the Earth's mantle...
bodies and lode gold deposits.
Gaspeite is reported from the Lord Brassey Mine, Tasmania, in association with hellyerite
Hellyerite
Hellyerite, NiCO3·6, is an hydrated nickel carbonate mineral. It is light blue to bright green in colour, has a hardness of 2.5, a vitreous luster, a white streak and crystallises in the monoclinic system...
.