This Miraculous medal and chain set is made of stainless steel The front of the medal depicts Mary standing on a globe, with the head of a serpent beneath her feet. Circling the oval-shaped medal is the signature, "O Mary, conceived without sin, pray for us who have recourse to thee." On the reverse, twelve stars surround a large "M," from which a cross arises. Below the "M," the medal depicts two flaming hearts. The left heart, circled with thorns, represents Jesus. The right heart, pierced by a sword, symbolizes Mary.The first medals were made in 1832 and distributed throughout Paris. According to the Association of the Miraculous Medal, the blessings that Mary promised "began to shower down" on wearers of the medal.