Undead MelodyFollow

I have had an item in my possession ever since I came to Qeynos. It's called "Undead Melody" and I have no idea what it is ( no luck on the search item here). It looks like a sort of necklace but I can't equip it and is LORE NO-TRADE and says it is a rare and expensive item. Anyone know what it is or what I can do with it?