You have found a tarnished necklace, though the tarnish belies intricate and magical craftsmanship.  The necklace has been shattered, as its setting appears to be missing three gems.  On the underside of the necklace is the faint imprint of the city seal for Ironforge.  Below the seal are three tiny, engraved letters: "TdK".$B$BIf there is anything to be gleaned from the necklace, you will need to learn about its origins.  Perhaps the seal and the initials are a start...