The "official birthstone" for the month of June, in western culture pearls have long been associated with the sacred (“pearly gates of heaven”), with purity, innocence and virginity -- symbolic meanings derived from the lustrous white color of the classic pearl and its relationship to water, which has the power to cleanse and purify.
Precious and rare in its natural form, the very word “pearl” has come to mean the finest example of something beautiful or valuable. Examples: “a pearl of a girl“ and “pearls of wisdom.” As far back as ancient Persia, excellent, intelligent ideas were called “pearls.” During imperial times in China, a natural black pearl was a symbol of wisdom.
Legends and Lore
There's a strange and lovely Persian legend about how pearls are created. The mollusk is said to rise to the surface of the sea at night. It opens up to a drop of rain infused with the light of the moon, which magically becomes the pearl.
Because they form in water, pearls are linked with water's power to nourish life. In ancient Greece/Rome, they symbolized Aphrodite/Venus, goddesses of beauty and love -- with emphasis on sexuality and fertility. Pearls were also associated with XiShi, a concubine in ancient China who was legendary for her extreme beauty.