Cronus stone

The Cronus stone is a green gem that controls time. It can allow anyone to freeze, slow, fast-forward or even travel through time.

In an alternate timeline created by Callisto, in which she prevented Hercules from being born, the Cronus stone ends up in Xena's hand, before her raid on Callisto's village. Because of Callisto's changes, Hercules never convinced Xena to change her ways and she had conquered the known world. She placed the stone on her scepter, not knowing its true value. Iolaus used it to saved Alcmene and prevent any of Callisto's actions from happened. But upon return to the present, she melts it.