The Raven Claw Talisman is crafted by a Fence after he has been sold the Old Brass Compass.
It is a helpful buff/perk that decreases weapon degradation by 20%.
You can obtain the Old Brass Compass by mailing in all 10 rock carving locations. Once you've obtained the Old Brass Compass, it can be traded for $29.00 at a Fence for the Talisman.
Glitches[]
There is a bug sometimes where the player can obtain the compass even before mailing the rock carving locations. Simply visit Francis' home at night. Sometimes there is a stranger corpse lying nearby his house. The player should be able to freely enter his house though the front door.