These hand painted metal hearts jingle when shaken and make a nice addition to a set of keys. Hearts are made from steel and a nikel-free metal alloy ring. ***SOLD Individually*** The heart has long been used as a symbol to refer to the spiritual, emotional, moral and intellectual core of a human being. As the heart was once widely believed to be the seat of the human soul, the word heart continues to be used poetically to refer to the soul and stylized depictions of hearts are used as prevalent symbols representing love.  The materials used to make these hearts follows the same testing for toys. Materials have been tested for lead, flammability and California safety standards.