may is a month of growth and beauty, and what better way to invite in this energy than with a birthstone charm? our serendipity may birthstone charm channels the properties of emerald, a vibrant gemstone that is said to promote love, fertility, and prosperity. add it to your favorite necklaces and bracelets to celebrate the abundance of life. this charm fits over most necklaces and the internal diameter is approximately 2.8 x 2.2 mm.