There is a reason engagement rings and diamonds are synonymous. With a chart-topping score of 10 on the Mohs scale — which ranks the relative ability of one mineral to scratch another — diamonds are durable enough to wear all day, every day.

Pearls, however, rank at just 2.5 on that scale. The organic gems are easily scratched and notoriously delicate.

“Pearl can be damaged by many chemicals and all acids,” the Gemological Institute of America warns in its pearl care and cleaning guide. “The list includes hair spray, perfume, cosmetics and even perspiration.”

So what does it say about the current era that pearl engagement rings are suddenly a thing?

In early December, Dave McCary, a “Saturday Night Live” producer, proposed to the actress Emma Stone (“La La Land,” “The Favorite”) with an 18-karat gold ring set with an 8-millimeter akoya cultured pearl. The pair proudly displayed the ring on Instagram.

And in early January, the four-time Oscar nominee Michelle Williams — recently engaged to Thomas Kail, the “Hamilton” director — was spotted in London wearing what was widely reported to be a pearl on her ring finger. (Her publicist would not comment.)

“We do see interest in pearls as engagement rings, part and parcel of a voracious appetite for pearls right now, I wonder if reimagining the pearl, which was co-opted for so long as very staid and traditional, is making them more modern and low-key and less fussy, and if that has any overlap with people’s desires to treat everything related to weddings the same way.”, a dealer commented.

In other words: These are not your grandmother’s rings.

“If you have a pearl engagement ring, presumably you’re taking it off periodically. Maybe that’s a fresh way to think about engagement rings? We see people being looser and more flexible.”

The diamond industry, however, is not in a panic. Diamonds still rule the engagement ring purchase — accounting for 83 percent of center stones, according to The Knot’s 2019 Jewelry and Engagement Study — even as the market for alternate bridal stones continues to grow, in step with all the other tradition-busting choices that mark modern nuptials (think multiple outfits rather than just one white gown, food trucks instead of three-course meals, and venues such as breweries and campgrounds in place of hotel ballrooms).

“When we think of alternative engagement rings, what we’re actually saying is that couples are prioritizing personalization across the entire experience, not just the wedding day,” said Kristen Maxwell Cooper, editor in chief of The Knot. “As more couples are discussing the engagement ring before the proposal happens, they’re both weighing in on what they want. Even if it’s a more delicate stone, like a pearl, they are choosing it because it speaks to them, versus saying, ‘I need a diamond solitaire.’”

Few people familiar with the current popularity of pearls would be surprised that they are being used in rings meant to endure. After all, fashion is utterly besotted with them.

Most people are equally familiar with the pearl’s other longstanding reputation: a matronly accessory, devoid of edge. And yet that very image is what charms some recent pearl fans.

“The thing that makes pearls cool is the grandma element,” said a Los Angeles jewelry designer. “I like all of those old things — like my name — that come back around.”

And therein lies the irony: When it comes to jewelry, there is nothing more classic than a pearl. Considered the world’s oldest gems because they emerge from their shells as finished products, requiring no cutting or shaping, the baubles have been sought after since the Middle Ages, as much for their beauty as for their mystical properties.

“They’re so commonly associated with purity, chastity and innocence,” said Beth Wees, a curator at the Metropolitan Museum of Art who worked on its 2018 exhibition “Jewelry: The Body Transformed.”

It light of such associations, it is easy to understand why pearls have long been used to accessorize the wedding party. From a modest pair of cultured freshwater pearl studs for the bride to a luxe strand of cultured South Sea pearls for her mother, the gems today possess a singular reputation for being both democratic and elitist.

Perhaps the evolution of pearls into bridal rings — less durable than diamonds, sure, but also orders of magnitude less expensive — was inevitable?

There are many reasons to believe in a pearl engagement ring, the pearl goes from day to night, from the soccer field to the ballroom. It is not blingy, yet fine pearls with wonderful luster do have properties we associate with gems. And pearls are the most sustainable gem on planet Earth: The cleaner the water and the better the ecosystem, the better it is for the cultivation of pearls.

From NY Times

The Arabian Gulf was the world’s first source of natural pearls and remained so for centuries. Natural pearls from the Gulf are notable for their transparent and high-luster nacre. Together with pearls from the Red Sea and the Strait of Manaar, they have been referred to as “oriental pearls” and are highly valued.

Part of a pearl’s appeal is its organic origins: It comes from a living animal, a mollusk. And because pearls are slightly porous, they warm up against the skin as they are worn. The wearer and the gems become one.

The exciting array of pearl choices available today can be overwhelming. When you combine the variety of colors, sizes and shapes with metals and other gemstones in rings, necklaces and earrings, the possible combinations are practically endless.

Pearls are natural or cultured and grow in mollusks that can live in either saltwater or fresh water. They are made up of layers of calcium carbonate most popularly in the form of nacre, a natural substance produced by pearl oysters that coats the inside of the animal’s shell. This beautiful, lustrous nacre is the very essence of a pearl.

Natural Saltwater Pearls
Natural pearls are extremely rare. The Arabian Gulf is the most important source for natural pearls – 70-80 percent of all pearls came from there until the 1950s. The island of Bahrain was a center for trade with northwest India and what is now the modern Middle East. A 4,000-year-old pearl was uncovered in 1989, and excavations at the ancient Bahrain’s Dilmun settlement have confirmed that pearl fishing has been going on for at least 3,000 years.

Natural saltwater pearls from the Arabian Gulf come from the Pinctada radiata and Pinctada margaritifera. Persian Gulf pearls range in color from white to dark cream and tend to be more yellow than those from the Red Sea and Strait of Manaar, whose characteristic colors are very light yellow, cream and very light pink. The Red Sea also produces some pearls in darker hues that range from intense pink to light to dark violet.

Natural saltwater pearls are also found occasionally in Baja California, Venezuela, Myanmar, China, Japan, India, French Polynesia, Australia and Africa – the same regions that have cultured pearl industries.

Saltwater Cultured Pearls
If you ask someone to describe an Akoya pearl, they will most likely describe a white, round, lustrous gem cultured in Japan and China in Pinctada fucata (martensii). Most akoya cultured pearls are white or cream and some have hints of rosé (pink) or green. The akoya oyster is relatively small, so it doesn’t usually produce a cultured pearl larger than 9 mm. Natural pearls from Pinctada fucata (matensii) are extremely rare.

Tahitian cultured pearls have only been on the market since the 1970s and come in colors including eggplant purple, peacock green, metallic gray and grayish blue. The mollusk that produces them (Pinctada margaritifera) is native to French Polynesia and is farmed there and in the Cook Islands, Fiji, Australia and New Zealand.

South Sea cultured pearls come from one of the world’s largest pearl oyster (Pinctada maxima), which produces cultured pearls that can measure 15 mm or larger. They are farmed in Australia, Burma, the Philippines and Indonesia. While South Sea cultured pearls occur in other colors, silver, white and yellow (sometimes referred to as “golden”) are the most common.

Freshwater Cultured Pearls
Cultured pearl farmers in China produce the overwhelming majority of cultured freshwater pearls. These cultured pearls vary widely in color and are generally more affordable than saltwater cultured pearls. Sizes are comparable to akoya cultured pearls, with a range between 2 mm and 13 mm, although larger sizes are now available. Fascinating new cultured pearls from fire balls to soufflés have been emerging from China in a dramatic array of colors.

The chief cultured pearl-producing mussel in the U.S. is the “washboard” M. nervosa. Only a small fraction of the total number of freshwater cultured pearls produced come from the U.S.

What to look for when picking out pearls

Size: As with other gems, a larger pearl (measured in millimeters) is typically more valuable. The larger the pearl, the more rare and costly it tends to be. But fine quality pearls can be small, and low quality pearls can be large, so a pearl’s ultimate worth depends on how it combines the complete mix of value factors.

Shape: While round is the most familiar shape, pearls come in a parade of forms (round, near round, oval, button, drop, semi-baroque, baroque). No matter what its shape, if a pearl is or symmetrical, it will be more valuable than one that’s irregular.

Color: A pearl’s color is a combination of its dominant bodycolor, overtone, the subtle colours that seem to come from within the pearl, and orient, the “play of color” you see when the pearl moves.. Cultured pearls display a broad palette of subtle hues, ranging from warm (yellow, orange and pink) to cool (blue, green and violet).

Luster: The intensity of light reflected from or just below the surface of the pearl, its luster, contributes the most to the beauty of a pearl. The effect is an inner glow from the heart of the gem. A pearl with excellent luster will look bright and shiny, while one with poor luster is dull and far less valuable. Fine akoyas tend to display a bright, mirror-like gloss. Other pearls tend to feature a softer, satiny luster.

Surface: A completely clean pearl is a rare treasure. Since rarity influences value, the prices of such pearls run extremely high. The number, nature, and location of surface characteristics (abrasions, bumps, chips, cracks, etc.) can affect the value of any pearl. Numerous or severe surface irregularities – such as chips or gaps – can threaten the durability of the pearl and cause it to break or peel and considerably lower its quality and value. If a surface characteristic is minor and located near a pearl’s drill hole, where it’s less noticeable, it will detract less from the pearl’s appearance and ultimate value.

Other value factors can minimize the effect of surface characteristics on a pearl’s worth. If the pearl is large and highly lustrous, for example, these pluses can outweigh a slight surface characteristic or two. In fact, excellent luster makes some surface characteristics less noticeable.

Nacre: Nacre is the very essence of the pearl itself and nacre thickness does affect the value. Quality cultured pearls have ample thickness to allow the pearl to display its beauty.

Matching: The uniformity of the appearance of pearls in strands and multi-pearl pieces is called matching.

How to Care for Pearls
Now that you’ve gotten your pearls, you should know a few things about taking care of them.

To retain their beauty, they need a certain amount of moisture, which is why you should avoid storing pearls in an airtight or overly dry environment, such as a bank safety deposit box. The human body conveniently provides just the right amount of moisture. Worn often and properly cared for, pearls can look as good in 50 years as they did the day they left the store.

Pearls are not the most durable of gems. Most everyday items at home and in the office are tougher than pearls, so careless contact can cause damage them over time. Chemicals are the primary threat. Perfume, makeup and hairspray contain ingredients that can eat away the nacre, permanently dulling it. Many cleaning products contain chemicals such as ammonia and chlorine, which can pit gold alloys and quickly damage pearls. Chlorinated swimming pool water is also hazardous. Avoid wearing pearl jewellery when cleaning the house or doing yard work.

The best way to clean your pearls is with a soft damp cloth, ideally after each time you wear them.

From GIA

Native Tahitians collected natural pearls from the black-lipped pearl mollusk, Pinctada margaritifera, for many generations prior to Spanish and English involvement. Some of these natural saltwater pearls reached the size of grapes. However, many decades passed before the rest of the world could enjoy their beauty.

The First Attempts at Tahitian Pearl Cultivation

In 1912, Kokichi Mikimoto, who had successfully cultured Akoya pearls, attempted to cultivate pearls in the black-lipped mollusk in the seas south of Japan. However, efforts to utilize this oyster failed until Jean-Marie Domard’s 1961 attempt in French Polynesia. Using the subspecies Pinctada margaritifera cumingii, his farm gathered the first harvest of cultured Tahitian pearls four years later.

The Growth of Tahitian Pearl Production

During the 1970s, Salvador Assael visited Tahiti. Recognizing the potential in these gems, he invested in the country’s pearl farms and production boomed. He introduced cultured Tahitian pearls to the United States. After the GIA certified their authenticity, these pearls became quite popular. Famous jewelers began to offer Tahitian pearls. Near the end of the decade, a strand of Tahitian pearls sold for $500,000. By 1985, fine strands could sell for a million dollars.

Responding to this new market, more and more pearl farms began operations. However, some of these farms produced low-quality pearls with extremely thin nacre. In certain cases, the nacre grew for only three months before harvesting.

In response, the government of French Polynesia enforced strict quality standards and taxes for any exported pearls. Those with too many surface imperfections or thin nacre would be destroyed, while others were sorted by quality and shape. These regulations ensured the quality and reputation of Tahitian pearls.

Characteristics of Tahitian Pearls

Tahitian pearls can show a wide range of body colors and overtones. Intense, dark colors make these pearls more valuable.

Body colors are generally gray or green and can be dark enough that the eye perceives black. Some have different body colors, like brown, copper, or dark blue.

These pearls also exhibit orient, a shimmering iridescence which seems to stay in place even as the pearl moves. This effect can be green, pink, blue, gold, or a combination of colors. Peacock orient, with both green and pink hues, is one common example.

Since they grow so large, they’re also rarely truly round. In fact, top-quality strands generally combine round and off-round pearls. Circle pearls account for about 35% of each Tahitian pearl harvest. These ringed pearls have their own beauty but don’t hold the same value as rounds.

What Sets Tahitian Pearls Apart?

Dark body colors and a mesmerizing orient make Tahitian pearls a unique jewelry option. While most other black pearls have undergone dye or irradiation treatments, these pearls achieve remarkable beauty without enhancements. With their large sizes, these luxury items can also make great statement pieces.

From Gem Society

From those ancient times until the discovery of the New World in 1492, some of the outstanding sources of natural pearls were the Persian Gulf, the waters of Ceylon (now Sri Lanka), Chinese rivers and lakes, and the rivers of Europe.

During Christopher Columbus’s third (1498) and fourth (1502) voyages to the New World, he repeatedly encountered native people adorned with natural pearls. His discovery of natural pearl sources in the waters of present-day Venezuela and Panama intensified demand in Europe. However, within a hundred years, these natural pearl sources had declined due to overfishing, pearl culturing, plastic buttons, and oil drilling.

The first steps toward pearl culturing occurred hundreds of years ago in China, and Japanese pioneers successfully produced whole cultured pearls around the beginning of the twentieth century. These became commercially important in the 1920s (about the same time natural pearl production began to decline). From the 1930s through the 1980s, pearl culturing diversified and spread to various countries around the world.

Pearls are treasures from the Earth’s ponds, lakes, seas, and oceans, and they’ve always embodied the mystery, power, and life-sustaining nature of water.
The spherical shape of some pearls led many cultures to associate this gem with the moon. In ancient China, pearls were believed to guarantee protection from fire and fire-breathing dragons. In Europe, they symbolized modesty, chastity, and purity.

(From GIA)