Produced by oysters in oceans or mussels in rivers, pearls have been coveted by humans since the Bronze Age. So much so that it is believed the exploitation of freshwater pearls was a factor in the Roman invasion of Britain in 55BC, as they were considered more valuable than diamonds.
Unfortunately, these days most marine and freshwater pearl species in the wild are critically endangered, with many on the Red List of the International Union for Conservation of Nature and Natural Resources (IUCN). Overharvesting and illegal fishing from fortune hunters, together with the degradation of their habitats, has brought them to the brink of extinction. Illegal fishing of oyster pearls in the wild — natural pearls — is no longer a concern, mainly because they are so rare that it is not worth the effort. However, the pillage of freshwater pearl mussels remains a big problem.
Evelyn Moorkens, a member of the IUCN’s Species Survival Commission, says the river Slaney, in south-east Ireland, had an estimated population of 10mn mussels when it was fished for pearls over a century ago. But, during the last survey conducted in 2023, only two live mussels were found, leaving little doubt over the role of pearl hunting in the demise of the species.
What has been an ecological tragedy has also been somewhat pointless from an economic perspective. “Pearls from freshwater mussels are worth very little in comparison to oyster pearls,” says Max Fawcett, head of jewellery for Emea at Christie’s. Pearl mussels are considered practically extinct in the UK, too, even though Scotland used to produce half of the world’s freshwater supply.
Efforts are being made to reverse the trend. Freshwater pearl fishing has been banned in Scotland since 1998, as well as in the EU, with several programmes desperately trying to help populations recover and ensure the species’ viability.
These wild pearls remain rare, though. One of the last jewellers with a licence to sell Scottish freshwater pearls, Cairncross of Perth, auctioned off its collection at Lyon & Turnbull last August. The star of the show was the Abernethy Pearl, a 10.91-carat specimen found in 1967, which achieved £93,951.
While that sounds impressive, Fawcett says a similar marine-cultured pearl — from an oyster grown in a human-controlled environment — would be far more desirable in today’s international market. And, if that pearl came from a wild oyster, the value would have been at least 10 times the freshwater equivalent.
Natural pearls are one of the rarest organic gems in the world and, as such, very much in demand. Oyster reefs are protected and subject to strict fishing regulations in most countries. Projects for the restoration of oyster reefs are showing encouraging results, but finding a wild pearl is almost a miracle.
Nikita Binani, a jewellery specialist at Sotheby’s, explains why: “Only one in 10,000 oysters in the wild would produce a pearl, with no guarantee of its quality. Finding a good one could easily take 20,000 oysters.”
That is why most jewellers use cultured pearls, which have the same properties as natural ones and are regarded as far more sustainable. “Oysters are filter feeders, meaning they clean the surrounding water by removing algae, plankton and organic particles,” explains José de Oliveira, general manager for Europe and the Middle East at jeweller Tasaki. “This process can improve water quality in the farming area, contributing positively to marine ecosystems. So, we believe that pearl farming, in itself, is sustainable.”
While Tasaki and Mikimoto cultivate their own pearls, most jewellers that work with these gems, including Harry Winston, Tiffany & Co and Adler, obtain supplies from sustainable sources that produce the highest-quality gems.
Tiffany, for example, chooses only from the top 5 per cent of South Sea, Tahitian, Akoya and freshwater varieties, while Adler says it sources its white pearls from Australia, pink and violet from China, golden from the Philippines, and the iconic black pearls from Tahiti.
The first modern cultured pearl was created in 1893 by the Japanese entrepreneur Kokichi Mikimoto. In the 1920s and 1930s, the cultivation of pearls grew significantly, as did their popularity. Coco Chanel wore them, Hollywood stars could not have enough of them, and Diana, Princess of Wales was a big fan.
By the turn of the 21st century, however, demand collapsed and prices tumbled. Cultured pearls were still highly coveted in Asia, especially India, but it was not enough to sustain high prices. “I remember a cultured pearl necklace that we sold in 1999 for $150,000 and 20 years later it didn’t reach $40,000,” says Fawcett of Christie’s. Today, the Asia-Pacific region accounts for 80 per cent of demand.
Prices are rising again, albeit slowly. Fawcett points out that “although cultured pearls may not be as rare as their natural counterparts, they still take a lot of time, manpower and specific climate conditions to harvest. Not all are of fantastic quality, so many are discarded or used for lesser jewellery.”
Climate change seems to be a big factor in how many are produced. “In recent years, the production of high-quality pearls has declined due to environmental challenges, such as ocean pollution, increasing sea temperatures, extreme weather events and that the number of pearl farmers is decreasing,” says Oliveira. Fawcett adds that “most of the South Sea pearl farms that used to be in Australia have moved to Indonesia due to the cost of labour and unpredictable weather such as typhoons, which can wipe out an entire crop of oysters”.
This should support prices. “If the conditions necessary for pearl farming continue to degrade, it is logical to expect that the prices of cultured pearls will keep increasing,” says Oliveira.
