Dean's Amulet

Dean's Amulet was a piece of jewelry given to him by Sam and, thus, meant a great deal to him.

Characteristics
The amulet has a metallic golden color and made of Brass. It depicts the head of a humanoid being with horns and tribal adornment. The amulet is worn using a black cord that easily goes over the head and into the neck of the wearer.

Season 3
An 8-year old Sam got the necklace from Bobby, intending to give it as a gift to John for Christmas. However when John didn't turn up, Sam gave it to Dean, who, since then, always wore it.

Season 5
Castiel, who was searching for God, turned up and informed Dean that the amulet that he wore was an indicator that could lead them to God; according to him, the head piece would burn hot in the presence of God. Dean handed him the amulet, albeit reluctantly, noting that he felt "naked" without it.

After the brothers returned from Heaven, Castiel came back to return the necklace, stating that it was "worthless". Dean, possibly disillusioned by how all of Sam's "happy memories" were ones away from him, dumped the amulet into a wastebasket on his way out of the motel.

Season 10
Although the original amulet is not recovered, at the end of a Supernatural play, Dean is given a replica which he hangs from The Impala's mirror.

Trivia

 * Fans arguing against Chuck Shurley's true identity primarily to the fact that Dean's amulet, which Castiel says will "burn hot" in God's presence does not react when Dean and Chuck meet face to face in The Monster at the End of This Book, Lucifer Rising, and Sympathy for the Devil. However, Joshua tells Sam and Dean in Heaven "Magic amulet or not, you won't be able to find him."
 * When interviewed at Paleyfest '11, Eric Kripke has stated: "There are no plans to return the amulet," before jocularly adding, "It's doing a guest shot on One Tree Hill," referring to its diva-like nature.
 * The amulet is visible during the flashbacks of Repo Man, Bad Boys, and Reichenbach.

Season 11

 * In Don't Call Me Shurley, it was revealed to be in God's possession and had been "turned off" to prevent his identity from being revealed.