Talisman

A talisman is a magical object thought to either protect or harm its possessor. They first appear in Storm Front.

Description
Often worn as amulets, talismans are meant to convey magical and symbolical forces to the warer; great care has to be taken that their construction closely reflects the intended purpose of the talisman and their simbolism to be in synthony with the forces they are in communion with.

Storm Front
In Storm Front, Harry Dresden wears a pentacle, which belonged to his mother, before investigating Victor Sells' lakehouse.

Victor Sells also sent him a dried scorpion talisman, which gets alive and stings Karrin Murphy, before hiding and ambushing Dresden himself.