Origins of the medals:

The Miraculous Medal, also known as the Rue du Bac Medal, is a Catholic medal associated with Marian apparitions and miracles. It takes its name from the apparition of the Virgin Mary to Catherine Labouré, a novice of the Daughters of Charity, in Paris in 1830.

According to Catherine Labouré's account, during the apparition, the Virgin Mary asked her to have a medal struck on which she would appear with specific inscriptions. The medal was therefore made according to the Virgin Mary's instructions, and it became famous for the many miracles and graces attributed to her intercession.

Symbol on the medal:

The Miraculous Medal is usually oval, with an image of the Virgin Mary on the front, standing on a globe, crushing a serpent with her feet. Around the image are the words in Latin "O Mary, conceived without sin, pray for us who have recourse to thee". On the back, there is a cross surmounted by the letter "M" intertwined with a cross, representing the heart of Jesus pierced by a sword and the heart of Mary pierced by seven swords. Around this image are the twelve stars of the rosary, as well as the initials "A" and "M" (for Ave Maria).

Wearing the Miraculous Medal:

The Miraculous Medal is often worn by Catholics as a sign of Marian devotion and trust in the intercession of the Virgin Mary. It is also often used in prayer and is associated with many accounts of healings and conversions.