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Formula: CuNi(CO3)(OH)2
Anhydrous carbonate containing hydroxyl, rosasite group,
nickel-bearing mineral
Crystal System: Monoclinic
Specific gravity: 3.78 to 3.96 measured
Hardness: 3 to 4
Streak: Pale green
Colour: Apple-green to malachite-green
Environments
Metamorphic environments
Hydrothermal environments
Localities
In Western Australia glaukosphaerite is apparently an indicator of
copper-nickel sulphide mineralisation.
Associated minerals include goethite,
secondary quartz,
paratacamite, gypsum,
nickel-bearing varieties of magnesite
and malachite, and clays.
Glaukosphaerite also fills joints in fresh basic rocks
(MM 39.737-743).
At the type locality, Hampton East Location 48, Kambalda Nickel mines, Kambalda, Coolgardie Shire, Western Australia,
glaukosphaerite occurs in green spherules of fibres. The
nickel mineralisation occurs in
greenstone
belts that have been invaded by basic to ultrabasic intrusives, also by later
porphyries and granites.
The whole assemblage has undergone metamorphism of
greenschist-facies grade.
Disseminated and massive mineralisation occurs towards the base of a
serpentinised dunite unit in
a zone of extreme talc-carbonate alteration.
Pyrrhotite, pentlandite,
chalcopyrite, sphalerite,
chromite and traces of galena
represent the primary assemblage while
violarite, secondary pyrite, and magnetite are
characteristic of the zone of supergene enrichment. In the zone
of oxidation glaukosphaerite, nickel-bearing
malachite, goethite,
quartz, manganese oxides, and
nickel-bearing chrysotile occur in
a weathered talc-rich outcrop
(MM 39.737-743).
At St. Ives gold camp, Kambalda, Coolgardie Shire, Western Australia, a specimen was found with a joint coating of
green 0.2 mm globules shown to be mainly nickel-bearing
malachite with some dolomite layers
and a few thin glaukosphaerite zones
(MM 39.737-743).
At Widgiemooltha, Coolgardie Shire, Western Australia, glaukosphaerite was first described in 1967, and was
determined to be a previously unknown carbonate of copper and
nickel, later named glaukosphaerite. Glaukosphaerite was also
collected in 1971 in the Widgiemooltha area, at the Dordie North nickel
prospect. Here it was intergrown with nickel-bearing
celadonite in veinlets in a
goethite-quartz-tremolite
rock
(MM 39.737-743).
At the Scotia Nickel Mine, Bardoc, Broad Arrow Goldfield, Kalgoorlie-Boulder Shire, Western Australia,
glaukosphaerite was found as films overgrown with quartz crystals on an
antigorite-talc-goethite
rock
(MM 39.737-743).
The Windarra Nickel Mine, Laverton, Laverton Shire, Western Australia, the scene of the celebrated Poseidon
nickel strike in August 1969, has also yielded glaukosphaerite specimens
that occur as thin veinlets in a
goethite-quartz-chalcedony
rock
(MM 39.737-743).
At the Carr Boyd Rocks Nickel mine, Menangina Station, Menzies Shire, Western Australia, glaukosphaerite was
associated with gypsum on an
actinolite rock. Subsequently it was found that the mine and surface dumps
are an
abundant source of glaukosphaerite in multi-hued green specimens of
paratacamite, gypsum,
nickel-bearing varieties of
magnesite and malachite and
clay. A specimen collected in 1972 was composed of green fibres up to 3 mm
long on a joint face of a weathered basic rock. The fibres proved to be glaukosphaerite with cores of
malachite
(MM 39.737-743).
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