Locking device for a bracelet or necklace

A locking device for bracelets and necklaces having two ends, each provided with a chain link, includes a first plate and a second plate which are pivotably coupled together for movement about a common pivot axis between an opening and locking position. The plates each have an aperture formed therethrough aligned with the pivot axis through which one of the chain links may extend and the first plate has a hook-like end portion for receiving the other of the chain links. The second plate has an arcuate slot formed therein running in a concentric manner with respect to the pivot axis which defines an arched portion on an end portion of the second plate disposed distal to the pivot axis relative to another end portion thereof. The arched portion also runs concentrically with respect to the pivot axis and, in the locking position, is received through the other chain link received in the hook-like end portion of the first plate.