The Collaborative International Dictionary of English v.0.48:

Niccolite \Nic"co*lite\, n. [from NL. niccolum nickel.] (Min.)
   A mineral of a copper-red color and metallic luster; an
   arsenide of nickel; -- called also coppernickel,
   kupfernickel.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Kupfernickel \Kup"fer*nick"el\, n. [G. See Copper, and
   Nickel.] (Min.)
   Copper-nickel; niccolite. See Niccolite.
   [1913 Webster]