Is a Nickel Arsenide often mixed with other sulfide minerals. In this case is Nickeline.The formula is Ni11As8. The color is grey-reddish with a metallic luster, very shiny when cut and polished and high specific gravity .Hardness is 5.
It comes from a type locality :Eisleben,Saxony-Anhalt,Germany.
Size: 8x6.7x4.2 mm.
Weight: 3.02 ct.