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Formula: Ni3Fe
Alloy, nickel-bearing mineral
Crystal System: Isometric
Specific gravity: 7.8 to 8.22 measured, 7.74 calculated
Hardness: 5
Streak: Light grey
Colour: Silver-white to greyish white
Magnetism: Strongly magnetic
Common impurities: Co,Cu,S,P,Si
Environments
Plutonic igneous environments
Placers
Metamorphic environments
Meteorites
Awaruite occurs in chromitite associated with
ultramafic igneous rocks, in river placers, in
serpentinised
peridotite, and rarely in meteorites. Associated minerals
include
gold and magnetite in placers,
copper, heazlewoodite,
pentlandite, violarite,
chromite and millerite in
peridotite, and
kamacite, allabogdanite,
schreibersite and graphite
in meteorites
(HOM). Awaruite is formed during the serpentinisation
of nickel-bearing olivine
(Dana).
Localities
At the Lord Brassey Mine, Heazlewood district, Waratah-Wynyard municipality, Tasmania, Australia, a seam of
high-grade heazlewoodite ore was encountered with
awaruite intergrown with the heazlewoodite
(AM 45.450-453).
At the Trial Harbour district, West Coast municipality, Tasmania, Australia, awaruite occurs in
association with pentlandite and
heazlewoodite
(Ramdohr).
At the Lewis Hills Massif, Bay of Islands, Newfoundland, Newfoundland and Labrador, Canada, in
harzburgite, dunite,
chromitite and
orthopyroxenite, rare base-metal phases occur as minute
wisps, flecks and grains in serpentine. Awaruite and
magnetite are the most common phases identified.
Pentlandite,
heazlewoodite, awaruite and
millerite occur in some
dunite. All the base-metal phases are believed to be of
secondary origin, related to
serpentinisation. Other reactions include the formation of
awaruite at the contact between pentlandite and native
copper
(CM 28.537-552).
At the Jeffrey Mine, Val-des-Sources, Les Sources RCM, Estrie, Quebec, Canada, awaruite is a common
accessory phase in most serpentinite of the asbestos-producing belt, and it developed during the
serpentinisation process from
nickel and iron already present
in the rocks. The largest grain of awaruite found measured almost 1 mm across.
Magnetite was generally found to be present in the same sections
as awaruite, though awaruite was not observed in actual contact with it. There seems little
doubt that awaruite and magnetite formed contemporaneously,
and repetition of the two-phase assemblages magnetite-awaruite
and magnetite-heazlewoodite
in different zones suggests an antipathy between awaruite and
heazlewoodite
(CM 8.519-522).
At the Allende meteorite, Pueblito de Allende, Chihuahua, Mexico, an opaque nodule enclosed in a
porphyritic olivine
grain in the carbonaceous chondrite comprises 9%
by volume of euhedral awaruite, 85% magnetite, 5%
pentlandite, and 1%
merrillite. The awaruite grains are zoned, with the centres
containing more cobalt than the edges
(AM 76.1356-1362).
At the type locality, the Gorge River, Westland District, West Coast Region, New Zealand, awaruite occurs
in serpentinite
(AJM 19.2.29).
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