Blind

The Blind Skull is the first of the Silver Skulls in Halo 3, and can be found in the first mission, Sierra 117.It is located relatively close to the beginning of the mission.

After your first encounter with the Gold Armor Brute, Two enemy dropships will appear a bit further down the stream. Go towards the dropship that is furthest away, and stay on the right side of the stream. Continue along the right (towards the cliff edge), and a rock will jut out a bit over the large lake. The Blind Skull is located on this rock.