The Arcane Signet Ring is an item first featured in the 3.5 edition's Eberron Campaign Setting and again in the 4th edition's Eberron Player's Guide. These rings are given to members of dragonmarked houses as means of identification. An Arcane Signet Ring is made from either silver or gold and appears to be an ordinary signet ring with gemstones embedded in it. Intricate patterns become visible when the ring is worn by the individual it was constructed for.
Though the item can only work through the means of magic, i.e. identifying who the wearer is and displaying a hidden image, the item does not appear in the list of magic items in either the Eberron Campaign Setting or Eberron Player's Guide. In fact it appears in the mundane items in the latter book.