A pearl is a hard, smooth, rounded (not necessarily round), lustrous object produced within the soft tissue of a living shelled mollusk or another animal, such as a conulariid.
Just like the shell of a mollusk, a pearl is composed of calcium carbonate in minute crystalline form, which has been deposited in concentric layers.
Pearls are valued as gemstones and are used in jewelry.
They are characterized by their translucence and lustre and by a delicate play of surface color called orient. The more perfect a pearl’s shape and the deeper its lustre, the greater its value.
There are essentially three types of pearls: natural, cultured and imitation.
Natural pearls form when an irritant – usually a parasite and not the proverbial grain of sand – works its way into an oyster, mussel, or clam. As a defense mechanism, a fluid is used to coat the irritant. Layer upon layer of this coating, called ‘nacre’, is deposited until a lustrous pearl is formed.
A cultured pearl undergoes the same process. The only difference is that the irritant is a surgically implanted bead or piece of shell called Mother of Pearl.
Imitation pearls are a different story altogether. In most cases, a glass bead is dipped into a solution made from fish scales. This coating is thin and may eventually wear off. One can usually tell an imitation by rubbing it across the teeth: Fake pearls glide across your teeth, while the layers of nacre on real pearls feel gritty.
Jewelers commonly refer to saltwater pearls as Oriental pearls and to those produced by freshwater mollusks as freshwater pearls.
Pearls come in eight basic shapes: round, semi-round, button, drop, pear, oval, baroque, and ringed.
Generally, the smallest pearls are as small as 2 millimeters (0.08 in) in diameter. Pearls usually have a maximum size range of approximately 14 millimeters in size.
The color of pearls varies with the mollusk and its environment. It ranges from black to white, with the rose of Indian pearls esteemed most. Other colours are cream, champagne, gray, blue, yellow, lavender, green, and mauve. All occur in delicate shades.
Pearls rank among the most popular gems in the world.
First recorded in history by a Chinese historian in 2,206 BC, pearls have been valued as gemstones for millennia.
Pearls symbolize wisdom acquired through experience. They are believed to attract wealth and luck as well as offer protection. The pearl is also said to symbolize the purity, generosity, integrity, and loyalty of its wearer.
The pearl is the birthstone of June, also the gem of the 3rd and 30th anniversary.
In a Christian New Testament parable (Matthew 13:45–46), Jesus compared the Kingdom of Heaven to a “pearl of great price”. “Again, the kingdom of heaven is like unto a merchant man, seeking goodly (fine) pearls: Who, when he had found one pearl of great price, went and sold all that he had, and bought it.”
Early Chinese civilization considered black pearls a symbol of wisdom and believed they were formed within a dragon’s head. Once full-grown, the pearls were carried between the dragon’s teeth. According to this myth, one had to slay the dragon to gather the pearls. The ancient Japanese believed that pearls were created from the tears of mythical creatures, such as mermaids, nymphs, and angels.
The ancient Egyptians prized pearls so much that they were buried with them. Cleopatra reportedly dissolved a pearl from one of her earrings in a glass of either wine or vinegar, depending on the source, and drank it. She did this just to show Mark Anthony that she could devour the wealth of an entire nation in just one gulp.
By the Middle Ages, pearls were considered sacred Christian objects due to their association with religious purity. Early Christians said the pearls covering the Holy Grail made its water pure.
The second largest pearl known was found in the Philippines in 1934 and is known as the Pearl of Lao Tzu. It is a naturally occurring, non-nacreous, calcareous concretion (pearl) from a giant clam. Because it did not grow in a pearl oyster it is not pearly; instead the surface is glossy like porcelain. Other pearls from giant clams are known to exist, but this is a particularly large one weighing 14 lb (6.4 kg).
The largest known pearl (also from a giant clam) is the Pearl of Puerto, also found in the Philippines by a fisherman from Puerto Princesa, Palawan Island. The enormous pearl is 30 cm wide (1 ft), 67 cm long (2.2 ft) and weighs 75 lb (34 kg).
The most expensive pearl ever sold was Marie Antoinette’s pendant. It sold for $32 million in a 2018 auction.