During the Renaissance, goldsmiths produced a new style of marriage ring known as the gimmel ring, which has two hoops that fan open from a pivot in the base.  When shut, the hoops of the gimmel ring slid together so perfectly as to become one ring, thus symbolizing the coming together of two lives truly as one.  Around 1600, the gimmel began to incorporate another romantic symbol, two clasped hands.  In the fede (the Italian word for “faith”) ring, the gimmel hoops ended in hands that clasped together when the ring was closed.  To this, yet another symbol was added – a heart.  In some of the more elaborate fede rings, delicately enameled hands were found to grasp a diamond heart.


P.S.  The Puritans tried to abolish the tradition of the wedding ring as part of their rebellion against church ritual.  It is testimony to the strength of the symbolism surrounding the custom that the wedding ring was too powerful to be destroyed.