The Miraculous Medal originated from apparitions of the Blessed Virgin Mary to St. Catherine Labouré, a Vincentian sister in Paris, in 1830. Mary appeared standing on a globe, crushing a serpent, with rays of light streaming from her hands, surrounded by the words: 'O Mary, conceived without sin, pray for us who have recourse to thee.' Mary instructed Catherine to have a medal struck with this image, promising: 'All who wear it will receive great graces.' The reverse shows the letter M beneath a cross, with the Sacred Heart of Jesus and the Immaculate Heart of Mary. Originally called the 'Medal of the Immaculate Conception,' so many miracles and conversions were attributed to it that people began calling it the 'Miraculous Medal.'