- align=center bgcolor="#9966FF"	Niccolite		- align=center	- align=center bgcolor="#9966FF"	General		-	Category	Mineral	-	Chemical formula	nickel arsenide:NiAs	- align="center" bgcolor="#9966FF"	Identification		-	Color	Pale copper red with blackish tarnish	-	Crystal habit	dihexagonal-dipyramidal rare; massive columnar to reniform	-	Crystal system	Hexagonal	-	Cleavage	absent	-	Fracture	uneven	-	Mohs Scale hardness	5 - 5.5	-	Luster	metallic	-	Refractive index	opaque	-	Pleochroism	N/A	-	Streak	brownish black	-	Specific gravity	7.8	-	Fusibility	2	-	Solubility	?	-	Other Characteristics	garlic odor on heating	- align="center" bgcolor="#9966FF"

Niccolite or nickeline is a mineral consisting of nickel arsenide, NiAs, containing 43.9% nickel and 56.1% arsenic.

Small quantities of sulfur, iron and cobalt are usually present, and sometimes the arsenic is largely replaced by antimony. Forms an isomorphous series with breithauptite (nickel antimonide).

The names niccolite (J. D. Dana, 1868) and nickeline (F. S. Beudant, 1832) refer to the presence of nickel (Lat. niccolum). Owing to its copper-red color the mineral is commonly called "copper-nickel," the German equivalent of which, Kupfernickel, was used as early as 1694.

Associated minerals include: arsenopyrite, barite, silver, cobaltite, pyrrhotite, pentlandite, chalcopyrite, breithauptite and maucherite. Niccolite alters to annabergite (a coating of green nickel arsenate) on exposure to moist air. Most of these minerals can be found in Cobalt, Ontario .

The following are the members of the nickeline group:^*

• Breithauptite: nickel antimonide, NiSb
• Freboldite: cobalt selenide, CoSe
• Imgreite: nickel telluride, NiTe
• Langistite: cobalt nickel arsenide, (Co,Ni)As
• Niccolite: nickel arsenide, NiAs
• Pyrrhotite: iron sulfide Fe_1-xS
• Sederholmite: nickel selenide, NiSe
• Stumpflite: platinum antimonide bismuthinide, Pt(Sb,Bi)
• Sudburyite: palladium nickel antimonide, (Pd,Ni)Sb

References and external links

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• Dana's Manual of Mineralogy ISBN 0471032883
• The mineral nickeline: Mineralgalleries.com
• Webmineral
• Mindat.org

Nickel minerals | Arsenide minerals

Nikkoliitti | Nickéline | Nikielin | Nikelín