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Awaruite is a naturally occurring
alloy An alloy is a mixture of chemical elements of which in most cases at least one is a metal, metallic element, although it is also sometimes used for mixtures of elements; herein only metallic alloys are described. Metallic alloys often have prop ...
of
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 ...
and
iron Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's o ...
with a composition from Ni2Fe to Ni3Fe. Awaruite occurs in river
placer deposit In geology, a placer deposit or placer is an accumulation of valuable minerals formed by gravity separation from a specific source rock during sedimentary processes. The name is from the Spanish language, Spanish word ''placer'', meaning "alluviu ...
s derived from serpentinized
peridotite Peridotite ( ) is a dense, coarse-grained igneous rock consisting mostly of the silicate minerals olivine and pyroxene. Peridotite is ultramafic, as the rock contains less than 45% silica. It is high in magnesium (Mg2+), reflecting the high pr ...
s and
ophiolite An ophiolite is a section of Earth's oceanic crust and the underlying upper mantle (Earth), upper mantle that has been uplifted and exposed, and often emplaced onto continental crustal rocks. The Greek word ὄφις, ''ophis'' (''snake'') is ...
s. It also occurs as a rare component of
meteorite A meteorite is a rock (geology), rock that originated in outer space and has fallen to the surface of a planet or Natural satellite, moon. When the original object enters the atmosphere, various factors such as friction, pressure, and chemical ...
s. It occurs in association with native gold and
magnetite Magnetite is a mineral and one of the main iron ores, with the chemical formula . It is one of the iron oxide, oxides of iron, and is ferrimagnetism, ferrimagnetic; it is attracted to a magnet and can be magnetization, magnetized to become a ...
in placers; with
copper Copper is a chemical element; it has symbol Cu (from Latin ) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orang ...
, heazlewoodite,
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,
chromite Chromite is a crystalline mineral composed primarily of iron(II) oxide and chromium(III) oxide compounds. It can be represented by the chemical formula of Iron, FeChromium, Cr2Oxygen, O4. It is an oxide mineral belonging to the spinel group. The ...
, and millerite in peridotites; with
kamacite Kamacite is an alloy of iron and nickel, which is found on Earth only in meteorites. According to the International Mineralogical Association (IMA) it is considered a proper nickel-rich variety of the mineral native iron. The proportion iron:ni ...
, allabogdanite,
schreibersite Schreibersite is generally a rare iron nickel phosphide mineral, , though common in iron-nickel meteorites. It has been found on Disko Island in Greenland and Illinois. Another name used for the mineral is rhabdite. It forms tetragonal crystals ...
and
graphite Graphite () is a Crystallinity, crystalline allotrope (form) of the element carbon. It consists of many stacked Layered materials, layers of graphene, typically in excess of hundreds of layers. Graphite occurs naturally and is the most stable ...
in meteorites. It was first described in 1885 for an occurrence along Gorge River, near Awarua Bay,
South Island The South Island ( , 'the waters of Pounamu, Greenstone') is the largest of the three major islands of New Zealand by surface area, the others being the smaller but more populous North Island and Stewart Island. It is bordered to the north by ...
,
New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...
, its type locality. Awaruite is also known as ''josephinite'' in an occurrence in
Josephine County, Oregon Josephine County is one of the 36 counties in the U.S. state of Oregon. As of the 2020 census, the population was 88,090. The county seat is Grants Pass. The county is named after Virginia Josephine Rollins (1834–1912), a settler who was t ...
where it is found as placer nuggets in stream channels and masses in serpentinized portions of the Josephine peridotite. Some nuggets contain
andradite Andradite is a Mineralogy, mineral species of the Garnet, garnet group. It is a Silicate minerals#Nesosilicates, nesosilicate, with chemical formula Ca3Fe2Si3O12. Andradite includes three varieties: * ''Colophonite'': a historical variety found ...
garnet Garnets () are a group of silicate minerals that have been used since the Bronze Age as gemstones and abrasives. Garnet minerals, while sharing similar physical and crystallographic properties, exhibit a wide range of chemical compositions, de ...
. An occurrence of awaruite was examined as an ore mineral in a large low grade deposit in central
British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...
, some 90 km northwest of Fort St. James. In the deposit awaruite occurs disseminated in the Mount Sidney Williams
ultramafic Ultramafic rocks (also referred to as ultrabasic rocks, although the terms are not wholly equivalent) are igneous and meta-igneous rocks with a very low silica content (less than 45%), generally >18% MgO, high FeO, low potassium, and are usua ...
/
ophiolite An ophiolite is a section of Earth's oceanic crust and the underlying upper mantle (Earth), upper mantle that has been uplifted and exposed, and often emplaced onto continental crustal rocks. The Greek word ὄφις, ''ophis'' (''snake'') is ...
complex.FPX Nickel Confirms Anticipated Timing for Completion of Preliminary Economic Assessment on Baptiste Nickel Deposit
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References

{{Reflist Native element minerals Cubic minerals Minerals in space group 221