As we begin a new season of auctions across our luxury and fine art categories, the Sotheby's Pricing Platform continues to drive estimates, valuations and exceptional results for our clients, in every collecting category. Here, we look back at how a small defect in a vintage Rolex Daytona turned it into a sought-after collectible that sold for four times its estimate in 2018.

W hat makes something a rarity? It could be the particular provenance of an object – perhaps it was owned by an iconic personality or it played a role in a famous historical event? It might be a particularly unusual work by a renowned master or be made from incredibly scarce raw materials. Maybe only very few of its like were ever produced, or that over time, only a small number have survived.

Sometimes rarity means an object is completely perfect...and sometimes, it's the imperfections that make it extra special. In the case of one Rolex watch, it was actually a small manufacturing flaw that transformed an already beautiful timepiece into one of the most desirable collectibles on the auction market.

In 1975, a Rolex Daytona ‘Paul Newman’ wristwatch, reference 6239 was the perfect 25th anniversary present from a wife to her husband. The pair were childhood sweethearts whose relationship survived the Second World War. They married in 1950, lived in India and Iraq where the husband continued to serve in the British Army and had two children together.

Costing £134, it was purchased with a cheque made out for £135 and the purchaser was issued with a £1 note as change, a receipt and the official Rolex certificate of authenticity. This original paperwork was all kept by the owner, who treasured the watch, wearing it every day on his way to work, when he would calculate the speed of his commuter train journey using the chronograph and landmarks along the track.

As a result of examining the watch face daily, he didn't notice at first that the colour of the three dials had begun to fade from black to a rich brown. When the gradual colour change was pointed out to him years later, he was initially dismayed – to a layperson the watch appeared to be diminishing in value. It was only through a chance meeting on a visit to a local jeweler that this owner discovered that the unusual new patination had in fact turned the wristwatch into a rare collectible.

The tell-tale toffee brown colour – known as a "tropical" dial – is in fact the result of chemical imperfection in a defective paint used in manufacture, that reacts with light. Only a very limited number of dials display this caramel colour and it has subsequently become one of the most coveted features in the auction market.

In its presentation case, complete with the certificate, receipt and one pound note change, the watch went to auction in Geneva in May 2018. with an estimate of CHF 200,000–400,000 ($208,000–416,000),. After a tense bidding it sold for CHF 951,000 ($947,776) – four times the low estimate.

When Rolex launched its Reference 6234 chronograph in 1955, it wasn’t a particularly successful model. However in 1962, the brand became the official timekeeper for the world famous Daytona motor race in Florida and a year later, Rolex launched a new chronograph reference, the Cosmograph 6239. Designed – with racing drivers in mind – to be precise, reliable and robust, it quickly became nicknamed the “Daytona”.

Popularity of the model skyrocketed once it became synonymous with Hollywood actor Paul Newman, already a devotee of Rolex pieces. Newman’s wife, the actress Joanne Woodward, gave him a new Cosmograph Daytona, reference 6239 fitted with an exotic dial to mark the beginning of his motor racing career in 1972. Subsequently, he was so frequently photographed wearing this model that it gained another nickname – the “Paul Newman”. The model has become hugely popular in the vintage watch world and is easily recognised by the white or black dial with contrasting subsidiary dials and outer minute ring.

When it was first purchased in 1975, this particular Daytona was already something special: a gift between loved ones, a luxury, a treasured possession and something that became synonymous with its owner, worn every day. If the story ended there, it would still be a charming and timeless item to own. But chance intervened and the special was elevated to the extraordinary, even if it took an expert eye to reveal that what appeared to be a defect was actually a blessing in disguise.

Watch the home video of the family's response to the auction bidding

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