To see a world in a grain of sand and heaven in a wild flower, hold infinity in the palm of your hand and eternity in an hour. -William Blake. Your spirituality is on display with Emerald infinity jewelry. The birthstone of May, an emerald ring symbolizes the eternally returning spring. The velvety green color of emerald is a perfect match for spring and summer fashions. Sapphire is the birthstone of September, and pink sapphire is a very popular gemstone in jewelry today. The bright and happy color of a pink sapphire ring is both playful and trendy.