This little French statue of Saint Mary currently available on Sacred Art & Antiquities depicts her serene beauty. But if you look at her feet, she is crushing a snake. The origins of this depiction go back to early translations ~ actually mistranslations ~ of Genesis 3:15.
The original Hebrew and Greek texts of Genesis 3:15 has God telling the serpent responsible for the fall of Adam and Eve that "... he shall crush your head and you shall lie in wait for his heel." However, both the Latin Vulgate and ancient Coptic translations have God's words as: "She shall crush your head."
The Q&A forum CatholicJules.net discusses Mary standing on the serpent:
Naturally in the Latin tradition, because of the translation “she shall crush,” the passage has had a more vivid Marian meaning. That’s where the tradition of depicting Mary crushing the head of the serpent arose. But it’s a very apt and theologically precise image, nonetheless, since it’s a perfect image of her Immaculate Conception, her lifelong immunity from sin, won for her by Christ’s saving passion and death on the cross (cf. Luke 1:47). This is one reason why the new liturgy of the Roman Rite, promulgated at Vatican II, retains the reading “she will crush your head.”
This Mary statue currently is available in the Statues & Santos section of Sacred Art & Antiquities.com.