The Blank Lexicon is a miscellaneous item given to the Dragonborn by Septimus Signus during the quest "Discerning the Transmundane." It can be used to activate a Dwarven Mechanism found in select Dwemer Ruins to gain access to Blackreach.

It must be given to Septimus Signus in order to retrieve the Oghma Infinium. The Blank Lexicon turns into a Runed Lexicon after finishing the quest "Discerning the Transmundane."



  • If it is taken back from Septimus' corpse, it may get stuck in the inventory, listed as a quest item. The same can apply to the Attunement Sphere as well.