Although described as a holy "book" of the faith, the Balance of Belaros took the form of a set of bronze scales that appeared to float effortlessly without any means of physical support. Both the beam and the pans of the Balance appeared to float without any chains or other apparatus suspending them. The entire artifact could be moved merely by towing the object by its main beam, but the component parts themselves could not be separated by any known means. The object appeared also to be impervious to corrosion or physical damage, and those that attempted to harm the object found the damage reflected upon themselves instead.
The sole known purpose of the Balance was to receive offerings, which, when placed in one of the pans, promptly vanished. If the offering was deemed worthy, one of a number of predetermined spell scrolls would appear in the opposite pan. Offerings of wealth or weapons seized from evildoers were considered particularly suitable.
The spell scrolls produced by the Balance of Belaros comprised the following: boon of the god, call upon faith, calm chaos, combine, detect charm, detect lie, detect magic, detect poison, dispel magic, draw upon holy might, emotion read, fire of justice, hammer of justice, make real, message mote, multiple message mote, personal reading, remove curse, sacred guardian, speak with animals, speak with dead, speak with monsters, stone tell, sword and hammer, tongues, true seeing, and zone of truth. The Balance never produced the same scroll twice in a row.
The eponymous creator of the Balance of Belaros lived sometime in the third millennium before Dalereckoning and is said to have hailed from somewhere in the vicinity of the Lake of Steam. Called the Mortal Hammer of Tyr, the smith Belaros created the Balance when he was already well into his sixth decade of life, after having retreated to a mountaintop near the northern border of Turmish to commune with his fellow veterans and—it was believed by the faithful—with Tyr himself.
The Balance was first housed in the High Hall of Justice in Treshla, a now-lost city located north of Saelmur and the Lake of Steam. When Treshla was utterly destroyed by a colony of beholders that descended upon the city in 1101 DR, the Balance remained for more than a century, floating unnoticed over the ruins, until it was spotted by a Calishite satrap passing by on a carpet of flying. The satrap, Ylearyn Glaermauz, transported the Balance back to his estate in eastern Calimshan, where it remained until the estate was in turn destroyed by trolls and the Balance was once again lost to history.
The Balance is known to have passed through the hands of the proprietor of the Masked Marilith, an antiquities shop in Saerloon, and been sold to the merchant rogue Luuthateel Dree, who wrongly believed that the Balance might help him achieve immortality. After being offered an ultimatum by a Tyrran priest to return the object, Dree fled, reportedly into the Underdark.
Since then, the object resurfaced briefly in markets in Silverymoon and Berdusk, but the object continued to elude the Tyrrans, who went so far as to accuse the Harpers of obstructing their efforts to recover the object. The Harpers denied having withheld the object, with Lady Cylyria Dragonbreast of Berdusk even volunteering to submit to questioning under a discern lies spell to dispute the accusation.