1) Nickeline 
• (n.) A mineral of a copper-red color and metallic luster; an arsenide of nickel; -- called also coppernickel, kupfernickel. • (n.) A mineral of a copper-red color and metallic luster; an arsenide of nickel; -- called also coppernickel, kupfernickel.
an ore mineral of nickel, nickel arsenide (NiAs). It is commonly found associated with other nickel arsenides and sulfides, as in the Natsume nickel ... [1 related articles]
Nic'co·lite noun [ from New Latin niccolum nickel.] (Min.) A mineral of a copper-red color and metallic luster; an arsenide of nickel; -- called also coppernickel , kupfernickel . 
Niccolite (nickeline) is an arsenide of nickel mineral with the formulae NiAs and a relative hardness of 6. It is a minor ore of nickel and often has a copper-like colour. It was confirmed as a distinct species in 1832, but was mined in the Middle Ages by miners believing it to be a copper ore.
Nickel arsenide
nickeline.