Pearl

History and lore

Pearls were treasured long before any gem was cut. Pearl fishing in the Persian Gulf around Bahrain and in the Gulf of Mannar between India and Sri Lanka goes back thousands of years, and divers there worked by breath alone until the twentieth century. In Rome pearls were the supreme luxury: Pliny the Elder says they held first place among valuables, and he tells how Cleopatra won a wager with Mark Antony by dissolving a priceless pearl in vinegar and drinking it. The story is probably embellished, since vinegar dissolves a pearl only slowly. Pliny also repeats the belief that oysters conceive pearls from dew, a cousin of the Indian tradition that pearls form when raindrops falling under the lunar mansion Svati enter a shell.

The Latin margarita gave the name Margaret, while the English "pearl" comes through Old French. In Europe natural pearls remained the most costly of jewels into the early twentieth century, when cultured pearls changed the market.

In the traditions

Jesus compares the kingdom of heaven to a merchant who, "when he had found one pearl of great price, went and sold all that he had, and bought it" (Matthew 13:46, KJV). In Revelation 21:21 each of the twelve gates of the New Jerusalem is a single pearl, the source of the "pearly gates". The Syriac Acts of Thomas (third century) contains the Hymn of the Pearl, in which a prince is sent to Egypt to recover a pearl guarded by a serpent, forgets his mission, and is awakened by a letter from his father; it is often read as an allegory of the soul in the manner of Gnostic thought.

The Qur'an describes pearl and coral coming forth from the two seas (55:22) and likens the youths of paradise to hidden pearls. In Chinese art the dragon pursues a flaming pearl, a symbol of wisdom and potency. In Vedic astrology the pearl (moti, Sanskrit mukta) is the Navaratna stone of the Moon, Chandra, and Agrippa likewise counted pearls among lunar things.

Meaning and symbolism

The American list of 1912 made pearl the June birthstone, alongside moonstone and, from 1952, alexandrite; some older lists place pearl under November (see June). It symbolises purity, wisdom won through hardship, and the Moon; a European superstition held that pearls given to a bride brought tears. These are traditional meanings rather than demonstrated effects.

The mineral

A pearl forms when a mollusc secretes layers of nacre, made of aragonite crystals and the protein conchiolin, around an irritant or a displaced piece of its own tissue. Natural pearls are now rare. Cultured pearls, developed in Japan in the 1890s and 1910s and associated above all with Mikimoto Kōkichi, are grown by inserting a bead or tissue graft. The main types are Akoya, South Sea (from Pinctada maxima), Tahitian black pearls (from Pinctada margaritifera) and freshwater pearls, mostly from Chinese mussels.

Rubbing a pearl gently against the edge of a tooth is a traditional test: nacre feels slightly gritty, while coated glass or plastic imitations feel smooth. Distinguishing natural from cultured needs X-ray imaging. Pearls are soft (2.5 to 4.5) and sensitive to acids, perfume, cosmetics and dryness; put them on last, wipe them after wearing, store them apart from other jewellery and have strands restrung regularly.

Sources and further reading

• Natural History, Books 9 and 37 — Pliny the Elder, c. 77 CE
• The Acts of Thomas (Hymn of the Pearl), Syriac, 3rd century
• The Book of the Pearl — George Frederick Kunz and Charles Hugh Stevenson, 1908
• Three Books of Occult Philosophy — Heinrich Cornelius Agrippa, 1533
• Brihat Samhita — Varahamihira, 6th century
• Gems: Their Sources, Descriptions and Identification — Robert Webster, 1962 (6th ed., ed. Michael O'Donoghue, 2006)