Graygem of Gargath
The Graygem of Gargath is an artifact that contains the essence of the being Chaos. Reorx created it to contain actually a small part of the god Chaos but accidentally captured him in the gem, according to the campaign setting. The artifact is the Graygem, which he puts into the moon Lunitari. The Gnomes took the Graygem to power a Great Machine they had made from Reorx's designs. The gem escapes them, and the Chaos within changes the world and the things in it (Pegasi, Minotaurs, etc.). The Gnomes chase the Graygem east from Taladas, until they reach Ansalon. Gargath, a powerful ancient wizard, traps the Graygem between two godstones and sets it in a tower. Two groups of Gnomes, one seeking the Graygem for wealth and the other wanting to study it, attempt to capture the Graygem from Gargath, and it transforms them into Dwarves and Kender. Palin Majere and his brothers attempt to capture the Graygem, and succeed, but their companion loses it again in a wager. The Irda find it and break it, accidentally bringing about the Chaos War.
Read more about this topic: List Of Dragonlance Artifacts