IT was an auction sale worthy of a celebratory dram. By the time the hammer fell on what whisky experts had dubbed “the perfect collection” of rare and vintage whiskies, more than £6.6 million had changed hands.

The star was The Macallan 1926 Fine & Rare 60-year-old. Sold for £1 million, it had slowly matured in its Spanish oak sherry cask while the world outside went battled through a world war, the Suez Crisis, the Cold War, a series of economic recessions and saw changing hemlines and the moon landings, before finally being bottled in 1986.

For whisky lovers and investors, the 3,900 bottles that made up the collection, sold a fortnight ago by Perth-based online auction house Whisky Auctioneer, was particularly prized because, having been lovingly curated over decades by an American whisky devotee, buyers could be confident that every drop was the real deal.

That, however, is not that case with for every bottle of supposedly allegedly antique and rare whisky which is arrives to be checked at Glasgow University’s SUERC Radiocarbon Laboratory in East Kilbride.

Indeed, according to Gordon Cook, Professor of Environmental Geochemistry, as much many as 40 per cent of the whiskies that have had the tiniest drop of their liquid gold contents carefully extracted by using a long syringe and checked using technology born from – of all things – research into the impacts of atom bomb tests, turned out to be fake.

And that is particularly concerning at a time when whisky is one of the hottest of commodities for investors seeking a stable place to put their money with the prospects of a good return.

“A lot of whisky from the 19th century up to the very early 20th century is making us nervous,” says Professor Cook, whose laboratory has tested the authenticity veracity of over 100 rare whiskies from auction houses and collectors.

“We have identified about 40% (of the whisky tested) as not being of the age that they were described. We estimate many were distilled around the 1960s to 1970s. Whiskies from the 1960s and 1970s are themselves potentially valuable but, in the wrong bottles, they are next to worthless.”

Not surprisingly, Prof Cook adds, breaking the news that a prized whisky is fake requires a sensitive approach. “People are upset. ” he adds. “Normally we tell them by email, so we don’t see their reactions.

“But I know I’d be upset if I paid £20,000 for a bottle of whisky and it turned out that it was worthless.”

The East Kilbride laboratory, which also carries out carbon dating analysis for police forensics and archaeologists, has developed a process first tried in the 1960s by Prof. Cook’s predecessor, Professor Murdoch Baxter, as part of work to measure the impact of the radioactive isotope carbon-14 on organic matter such as barley.

In those days, says Prof Cook, half a bottle of whisky would be required to measure the radiocarbon. Now, aided by millions of pounds’ worth of equipment, it takes just a few millilitres of liquid to tell whether the barley used in the distillation process grew before or after atomic bomb tests.

More recently, the lab has sampled dozens of genuine, rare whiskies to create a radiocarbon dating curve, in a move which has helped to pinpoint the actual age of whiskies to within a few years.

Now, to help further combat frauds, SUERC has partnered with London blockchain specialists Everledger, which will see NFC-powered tamper detection labels attached to confirmed vintage and rare bottles, creating a unique digital identity for it and its contents.

The partnership comes as vintage and limited-edition whiskies have soared in value, with the best attracting interest from ultra-high net-worth investors – worth with a net worth of over US $30 million or more – often from China and across the wider Asia-Pacific region.

Such is the buzz around antique and rare bottles that when the Knight Frank Wealth Investment Index, which tracks the progress and performance of collectable luxury items such as art, classic cars and wine, opted to include rare whiskies in 2018, Scotch overtook its rival products and shot straight to the top of the list. It’s led to a rise in the number of bottles being tested at the East Kilbride laboratory.

“There are people are concerned about that what they bought some time ago as part of a collection or investment. They are worried, so they have them analysed and find out they are fakes,” says Prof Cook. On the other hand, those confirmed as genuine can soar in value. “There’s advantage to doing the testing,” he adds. “Demonstrating it’s genuine adds value.”

Of course, just because 40% of bottles tested at the laboratory were confirmed as fake does not mean nearly half of rare whiskies in circulation around the world are frauds. However, there are concerns that whisky’s soaring value as an investment – particularly among middle-priced collectibles – will make the rare whisky sector even more attractive to unscrupulous forgers. Andy Simpson, director and co-founder of the whisky analyst and broker Rare Whisky 101, which has used the SUERC lab to test dozens of whiskies, suggests all bottles from 1900 and earlier should be radiocarbon dated.

Collectors in general should be conscious of the risks posed by fakes, he adds. “We’re not saying that 40% of rare whisky is fake – that’s not the case. But we are very much of the opinion that people shouldn’t just buy anything that purports to be distilled before 1900 without it being radiocarbon dated. It’s too big a risk. We assume guilty until proven innocent.”

Among the whiskies to be analysed – in an Oxford laboratory, the only other site in the UK carrying out whisky carbon dating – was a rare Macallan, apparently distilled in 1878 and on sale at the plush Waldhaus Am See hotel in St Moritz.

Andy tells how, having heard how a Chinese customer spent around £7000 for a dram, his firm asked if a small sample could be analysed and dated. It was fake.

He reckons there is around £41 million worth of fake rare whisky swilling around collectors’ cabinets. And, whilst most are fake Scotch single malts, collectable Japanese and American whiskies are also being copied. Indeed, middle of the range collectible whiskies are less likely to arouse suspicion than an ultra-rare antique Scotch, making them more likely to trick buyers.

“Over the last six years I’ve seen about £7.1m of fake whisky cross my desk. You just have to look online – you can see empty bottles of whisky for sale for hundreds of pounds. They will almost certainly be re-filled, re-closed and hit the market.

“We get phished by fakers or representatives of fakers. They say ‘my uncle died and I found these bottles in his loft, can you look at them?’ Then they’ll ask why it’s fake – they’re trying to assess the weaknesses in the label or bottle.

“We are probably seeing a relatively constant volume of fakes and we’re aware of increasing pools of stock of in Asia, Hong Kong and mainland China.”

He recalls one collector who approached RW101, seeking to sell his £1m million stash of whisky. “We had a batch of 10 radiocarbon dated. Not one proved genuine.

“It was not a good day for him, unfortunately,” he adds. “But we know pretty experienced collectors who have been duped.”

The quality of fakes can make them hard to spot with the naked eye. “One 1903 Laphroaig we had tested was fabulous. It was old glass, turn of the century bubbling, three-piece moulded bottle, label really well done. It looked brilliant.

“As soon as we opened it, we found it had a composite cork. It should have been whisky from the late 1800s, actually it was 2007 to 2010. That’s 100 years of difference.”

Alarm bells tend to ring when he sees the likes of an 18-year-old Gran Reserva Macallan from 1979, as he’s seen so many now that have proven to be fakes.

On the other hand, carbon dating whisky can throw up the occasional pleasant surprise – such as the 1920 Lagavulin which had been estimated to fetch around £4,000 but which soared to £11,500 at auction once its contents were proven to be genuine.

Isabel Graham-Yooll, auction and private client director at whisky.auction, played a key role in exposing a forger’s scheme to defraud whisky collectors of tens of thousands of pounds in fake bottles three years ago.

However, she doesn’t believe the vintage and rare whisky marketplace is flooded with fakes, or that testing and adding tamper-proof seals will halt the fraudsters.

“There’s a very healthy market for whisky; that in itself will attract the nasty people,” she says. “Here, we reject one or two bottles a week as fake – that’s less than 1% of the bottles that we sell.”

Auction house experts are skilled at spotting potential frauds, she adds. “Sometimes it’s a photocopied label or wrong combination of features. The most common thing to find is someone has refilled the bottle – you don’t need technology to spot that, you just need to have a keen eye.”

There is, she concedes, an ongoing problem of fraud and fakery. “I liken it to an arms race,” she says. “The thing you do to prevent fraud is the very next thing the fraudsters will look at beating. To them, it’s a bit of a game.”