The Darkstone Tablet holds the writings of the long-dead dwarf Urheld Darkstone.  An alchemist of great skill, he was thought insane by his contemporaries and, hence, did not share his research.$B$BBut he did etch it onto tablets, and I believe one such tablet lies in Blackrock Spire, in a chamber once named the Hall of Fortune.  I know not what it is now called, for few enter Blackrock and return.$B$BBut if you are willing to brave its dangers and return to me with the tablet, your reward will be great.