The snake eating it's own tail, or Ouroboros, has symbolized many things over the ages, but generally represents ideas of recreation of self, unity, and infinity. The ouroboros has been important in religious and mythological symbolism world wide. The Ouroboros appeared in Ancient Norse mythology as one of the children of Loki, who grew so large that it could encircle the world and grasp its tail in its teeth.
The snake appears to be going through your ear. The hoop style earring measures approximately 20.5 mm (13/16") in diameter and 5.4 mm (just under 1/4") wide at the snake's head. The ouroboros weighs approximately 2 grams.