Are Pearls a Good Investment? What Auctions and the Market Say

The pearl market is made up of two worlds. In one, a bidder at Sotheby's in Geneva paid around 36.2 million dollars in 2018 for a single pendant that once belonged to Marie Antoinette. In the other, a well kept Akoya strand, bought ten years ago for 2,000 euros, lies on a buyer's counter and brings in a few hundred euros. Anyone who views pearls as an investment needs to know which of these two worlds their own piece belongs to.

What the auction houses are actually selling

Anyone looking for proof that pearls hold their value as an investment will find it almost exclusively among natural pearls. These are pearls that grew in the mollusc without human intervention, unlike cultured pearls, where a bead nucleus or a piece of mantle tissue is inserted. Marie Antoinette's pendant, a drop shaped natural pearl around 2.58 cm long set with diamonds, was estimated at Sotheby's in Geneva at 1 to 2 million dollars. On 14 November 2018 the price with buyer's premium came to 36,427,000 Swiss francs. The queen's ten pieces together brought 43.1 million francs against an estimate of 1.6 to 2.9 million.

The second reference case is the Cowdray Pearls: 42 graduated grey natural pearls between 6.65 and 12.90 mm, mounted by Cartier, with two reports from the Swiss laboratory SSEF dated April 2013. Christie's London sold them in June 2012, then strung with 38 pearls, for 3.35 million dollars. The necklace was afterwards restrung to its original 42 pearls. In October 2015 it fetched 5.27 million dollars at Sotheby's in Hong Kong, a gain of around 57 per cent in just over three years, and it has held the auction record for a grey natural pearl necklace ever since.

The Christie's sale of 11 June 2024 in New York stands out. There, five natural pearl lots came in at between 2 and 9 times their high estimate. Those who want the full story behind these records will find it under the most expensive pearls in the world.

Why retail cultured pearls lose value on resale

The strand from the jeweller's shop follows different rules. Its shop price includes the clasp, the stringing, the dealer's margin, VAT and often a brand name. On resale none of that counts any more. Only the material value of the pearls remains, and a buyer measures that against the wholesale price. Trade figures put resale proceeds for cultured pearls bought at retail at 30 to 40 per cent of the original shop price when a specialist dealer takes the piece. For medium and basic qualities the proceeds are often lower, because the supply of second hand Akoya and freshwater strands is large and demand on the secondary market is small.

A historical example shows that even natural pearls are not immune to market shifts. A natural pearl necklace bought in 1917 for around 1 million dollars was auctioned in 1957 for 157,000 dollars. In between, the cultured pearl had reached the market and depressed the price of natural pearls for decades. Only with reliable X-ray methods and a growing awareness of how rare old natural pearls are did the curve turn upwards again.

Why Akoya and Tahitian prices swing so sharply

Anyone who still regards cultured pearls as an investment needs to understand the production side, because that is where the price swings originate. In Japan, Akoya oysters died in large numbers in the summers of 2019 and 2020. A study published in 2021 by Japan's fisheries research agency puts mortality among juvenile oysters in Mie Prefecture at 56 to 74 per cent, compared with 15 per cent in a normal year. A pearl farm in Ise-Shima reports that the volume farmed in Ehime and Mie fell by around 80 per cent and that prices for Akoya pearls rose by 50 per cent and more.

Tahitian pearls from French Polynesia show the other side of the same coin. According to the statistics institute ISPF, around 17 tonnes of raw cultured pearls were exported in 2023 for 17 billion CFP francs, roughly 142 million euros. The average price per gram rose from 690 CFP francs (2022) to 980 CFP francs (2023), about 8.20 euros. A year later the market turned: in 2024 the export value fell by 59 per cent to just under 7 billion CFP francs, the volume by 52 per cent, and in the fourth quarter the price per gram stood at 700 CFP francs. Anyone who bought Tahitian pearls at the 2023 peak is now sitting on a paper loss.

What makes a piece hold its value

Pearl jewellery holds its value when as many of the following features as possible come together. If the first is missing, the rest carry little weight.

• Natural pearl with a laboratory report: a report from GIA, SSEF or Gübelin confirms by X-ray that there is no nucleus and no treatment. Without a report, a natural pearl is traded like a cultured pearl.
• Size: natural pearls over 10 mm are rare. Among cultured pearls, South Sea pearls from 13 mm and Tahitian pearls from 12 mm are the sought after sizes.
• Nacre thickness: for Akoya pearls the trade regards 0.15 to 0.50 mm as usual; dealers grade from 0.5 mm as AA+ and from 0.7 mm as AAA. Thin layers age faster and destroy the value.
• Provenance: ownership by a historical figure or a famous house multiplies the price. Marie Antoinette's pendant fetched 18 times its high estimate.
• Signature and original condition: mounts by Cartier, Tiffany or Mikimoto with case and papers achieve better prices on the secondary market than anonymous pieces.
• Colour and rarity: grey natural pearls such as the Cowdray Pearls, and Melo or conch pearls, which do not exist in cultured form, are collecting fields in their own right.

The difference between a natural and a cultured pearl cannot be seen with the naked eye, only in an X-ray image. How the laboratories go about it is explained in natural pearl or cultured pearl.

The laboratory report decides on market access

Every top lot in the auctions mentioned carries a laboratory report: the Cowdray Pearls two SSEF reports, the Tiffany necklace at Christie's a GIA report from 2024 confirming 61 untreated saltwater natural pearls. GIA describes microradiography, a fine X-ray image of the pearl's interior, as the most reliable non destructive method for separating natural from cultured pearls. The report thus becomes part of the value itself. Measured against hammer prices that reach multiples of the estimate, the report is a small outlay, and it opens the door to the only market in which such prices are possible at all.

For heirlooms without papers, an examination is therefore worthwhile before a buyer names a price. What an appraisal and a laboratory report cost, and where they make sense, is set out under having pearls appraised. A word of caution: in 2025 GIA reported hybrid Akoya pearls with 1.62 to 1.68 mm of nacre around a tiny nucleus, whereas 0.15 to 0.50 mm is usual in the trade. Such pearls cannot be told apart from natural pearls with the naked eye or even by weight; only the X-ray reveals the nucleus. Buying without a laboratory report therefore remains a risk.

An honest assessment

As a financial investment in the sense of yielding a return, pearls are suitable only in the top price bracket, and even there only with patience, a laboratory report and an auction house as the sales channel, which itself retains a buyer's premium and a seller's commission. For all other pieces the rule is: the purchase is consumption, not investment. A good Akoya or South Sea strand loses part of its shop price after purchase and then holds that residual value for decades, provided it is looked after.