THE largest Scottish freshwater pearl “found in living memory” is set to go up for auction as part of a collection from an iconic jewellers which closed in 2023.

Known as the Abernethy pearl, after its finder William Abernethy, is to go under the hammer on August 21 – and is expected to fetch between £40,000 and £60,000.

The freshwater pearl, which was discovered in 1967, is being sold as part of a collection of pieces from the renowned Scottish jewellers Cairncross of Perth, which closed last year after more than 150 years in business.

Auctioneers Lyon & Turnbull will auction the full collection including the Abernethy pearl, which weighs 43.6 grains – with one grain equal to one-quarter of a carat, or 0.05 grams.

Ruth Davis, the head of jewellery at Lyon & Turnbull, holds the Abernethy pearl (Image: Stewart Attwood)

Abernethy, who died in 2021 aged 96, never disclosed exactly where in Scotland he made the rare find. It is believed that it may have been growing for 80 years before it was discovered.

It’s thought that only one in every 5000 mussels found in Scottish rivers contains a pearl, and generally they are smaller than their saltwater cousins.

Award-winning wildlife cameraman Doug Allan remembered working with Abernathy in the 1970s – before pearl fishing was banned in Scotland outright in 1998.

"Bill was a unique man and it was a privilege to have known him,” he said. "I recall watched Bill fishing with his glass and stick and then he gave me a go. It didn’t take long to appreciate just how much hard graft it was.

"Bill, of course, made it look effortless. Which it wasn’t. He'd be there, bent over the glass, peering down at the river bed, picking out the small lips of the shells that were buried in the sand.

"I loved learning something of the old craft from Bill. The old words that only the real pearl fishers would use. We’d walk sometimes for miles over the fields until we reached the 'the spot'. He’d point out the specific part of the river that he knew would be best for pearls."

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Ruth Davis, the head of jewellery at Lyon & Turnbull, said: "The Cairncross Collection offers a final opportunity to obtain a piece of Perthshire history.

"As well as antique jewellery, including a beautiful pair [of] diamond stud earrings, weighing over 4.00cts, the collection also includes more contemporary pieces, from high-end designers such as Picchiotti and enamelled jewels by Victor Mayer, as well as a selection of Scottish river pearls.

"The Abernethy Pearl is, of course, the star of the sale and we’re excited to see the interest the auction will undoubtedly generate."

Lyon & Turnbull noted that the Kelly (or Kellie) Pearl, which is part of Scotland’s crown jewels, still holds the record for the largest freshwater pearl ever found in the country.