Nickel
Nickel is an element, atomic number 28 on the 21st century periodic table. 

The water of a planet in the Gamma Quadrant surveyed by Nog and Jake Sisko in 2370 contained traces of nickel, copper and birythium, plus lead from the surrounding soil. ()

Many planetary cores are composed of an iron-nickel alloy, either in solid or liquid form. 

The planetoid in the Gamma Canaris region where Zefram Cochrane lived with the Companion is composed of iron and nickel. ()

A M-class planet located in the Ngame Nebula that was terraformed by the Paxans and discovered by the  had a nickel-iron core. ()

Sensor scans of the asteroids artificially constructed by the Etanians, used to attack a Nezu colony, showed that they were composed of a simple nickel-iron composite. ()

A planet that the  crashed on in 2375 had a Class M atmosphere, nickel-iron core, and bemonite mantle. ()

External links
 
 

de:Nickel
Elements