G'axir the Seer (quest)

You acquire this quest by speakint to G'axir the Seer in the Blade and Stars tavern in BG. He wants you to bring him a Sphene Gem from the greater basilisk. The basilisk is located in the northern warehouse in BG docks. To kill him you can use potion of mirrored eyes, protection from petrification spell or items that provide bonus to save vs petrification rolls, like Adoy's Belt, Claw of Kazgaroth or protection ring / cloak.

The basilisk is also the atrget of the Basilisk on the Loose quest.