Our Lady appeared to 24 year old Catherine Labouré, a nun with the Daughters of Charity of St. Vincent de Paul and St. Louise de Marillac, in Paris, on the 27th of November 1830.

In the vision, Our Lady was standing on a globe with Her arms outstretched. From the back of Her hands, streaming rays of dazzling light flowed. Around Our Lady was the inscription “O Mary, conceived without sin, pray for us who have recourse to thee.”

Our Lady then instructed Catherine; “Have a medal struck upon this model. Those who wear it will receive great graces, especially if they wear it around the neck.”

The vision then seemed to turn to show the reverse of the Medal: the letter M surmounted by a cross with a bar at its base; below this image were two hearts, one crowned with thorns, and the other, pierced with a sword.- representing the Sacred Heart of Jesus, and the Immaculate Heart of Mary.

The Front
• Our Lady stands on a globe, crushing a serpent beneath her feet. Describing the original vision, Catherine said the Blessed Mother appeared radiant as a sunrise, “in all her perfect beauty.”
• Rays shoot out from Mary’s hands, which she told Catherine, “… symbolize the graces I shed upon those who ask for them.”
• Words from the vision form an oval frame around Mary: “O Mary, conceived without sin, pray for us who have recourse to thee.”
Seen as a matrix, the elements of the front design encapsulate major Marian tenets:

Quality of Our Lady As Illustrated by the Medal
• Mother — Her open arms, the “recourse” we have in her.
• Immaculate — The words, “conceived without sin.”
• Assumed into Heaven — She stands on the globe.
• Mediatrix — Rays from her hands symbolizing “graces.”
• Our Protection — Crushes the serpent (Gn 3:15).

The Reverse
• A cross-and-bar surmounts a large, bold “M.”
• 12 stars disperse around the perimeter.
• Two hearts are depicted underneath the “M,” the left lapped with a crown of thorns, the right skewed by a sword. From each, a flame emanates from the top. Again, employing a grid analysis, we can see how the reverse-side design contains great symbolism reflecting major tenets of the Catholic faith.

Design Element and its Catholic Meaning
• The large letter “M” — Mary as Mother, Mediatrix.
• Cross and bar — Jesus’ Cross of Redemption.
• 12 stars — 12 Apostles, who formed the first Church.
• Left Heart — The Sacred Heart, who died for our sins.
• Right Heart — The Immaculate Heart, who intercedes for us.
• Flames — The burning love Jesus and Mary have for us.