Where is the stone of Golorr?

It is said that Dagult Neverember stole a lot of gold from the city of Waterdeep when he stopped being the Open Lord. He hid it. People say that it can be found using the Stone of Golorr.

Renaer Neverember said that the Xanathar Guild had the stone, but that it was recently stolen. The Zhents thought that Renaer knew something about all of this, so they abducted him. Then Xanathar bandits attacked the warehouse where they held Renear and Floon Blagmaar, and they abducted Floon.