Zrbite is an organic mineral substance from X-Com: Terror from the Deep, which plays the same role as Elerium-115 as the Alien's Power Source. It is exceptionally important in manufacturing equipment and subs that incorporate alien technology.
Zrbite is a highly reactive mineral substance made from a blend of Gold and an unknown organic Alien Substance. One lump of this precious metal can produce more energy than about a ton of weapons grade uranium. However, since it is impossible to replicate this substance by normal means, the only way to obtain more Zrbite is to liberate it from Alien Subs or undersea Colonies.