When inert, the chaos stone is charcoal gray in color. When touched by someone of chaotic alignment, the stone springs to life with color. The color is unique to the bearer.
However, chaos stones are not unique, just extremely rare. Much like its color, the powers of a chaos stone are unique to the bearer. The purported powers of the stone are so varied it is uncertain whether wielding one will provide the bearer with ultimate power or spontaneous, uncontrolled levitation. There are no tales of one creature controlling multiple chaos stones.
A lawful creature that attempts to touch the stone will feel overwhelmed with a sense of impending doom. If foolish enough to wield it, the stone remains inert, but bestows two temporary negative levels upon the lawful creature.
A creature that is neither lawful nor chaotic experiences the same feelings and fate, but to a lesser degree. The neutral creature foolish enough to wield the chaos stone receives one temporary negative level.
You found a chaos stone embedded in a statue of a handmaiden of Kelek in the Smuggler’s Temple. After the statue slew the temple’s high priest, Avir, the stone fell from the statue’s brow and became inert.