The episode of the Cottingley Fairies did nothing to enhance the reputation of Sir Arthur Conan Doyle, who was taken in by the hoax along with many others, and widely ridiculed as a result.

It all started in 1917 when cousins Elsie Wright, aged 17, and Frances Griffiths, aged nine, took photos of themselves in their garden with what appeared to be dancing fairies and a tiny gnome. In fact they were cleverly crafted coloured cut outs supported by hatpins, but enough people were taken in by the trick for serious discussions about the existence of fairies to arise over a number of years. Conan Doyle went into print more than once on the subject. Around 20 years ago a film of the story was released.

Now the two images are coming up for auction with hopes of £2000.

It’s astonishing a century on that so many people could have been taken in by the hoax, but I believe Conan Doyle should be seen in a more sympathetic light. He had already lost a wife and son and developed a serious interest in spiritualism over a period of 30 years. The thought of life after death and the possibility of being able to contact lost loved ones must have been highly appealing and a great comfort to him.

The Cottingley Fairies episode would have added to his fascination and research and he was keener on being remembered for this side of his life than for his fiction.

It used to be all about the Three Ds – Death, Divorce and Debt – when it came to reasons for consigning to auction. Now you can add Downsizing and De-cluttering as modern tastes moved towards minimalism in the home and older couples cashed in their property portfolios once the children had flown the nest.

I was reminded of all of these this week as news emerged of a sale that has arisen as a result of Debt. Adding another D – this time for Disaster – the theme of the sale will be the Titanic, whose sinking was a unique event in history that continues to fascinate and horrify in equal measure owing to both the sheer scale of the loss of innocent life and its symbolism. Few catastrophes (the 2004 Boxing Day tsunami was another) better illustrate the lasting truth that no matter how developed and sophisticated we become as a species, humans are only ever a small step away from the unstoppable caprice of nature.

In this case a company specialising in exhibiting Titanic memorabilia has filed for bankruptcy, leaving all the exhibits up fro grabs. When you consider that the violin played by the bandleader as the ship sank sold last year for $1.7 million (it’s not part of this sale) the attraction of Titanic items becomes obvious.

However, putting all the pieces on the market at once risks deflating values, so it will be interesting to see how the administrators handle the auction.

I’ve written before about how some of the most valuable collectables arise out of their rarity – sometimes because they were deliberately produced in tiny editions to create such a demand, but also because they were withdrawn after a short run because of mistakes or proved undesirable at the time. Two examples of the latter are The Exploding Trench, a WWI toy that manufacturers Britains made the mistake of filling with British rather than German model troops, and the Vinyl Cape Jawa figure, a minor character from Star Wars, soon replaced by one dressed in a cloth cape.

Such limited editions are common in the world of stamps (the Inverted Jenny), coins and bank notes too. In the news this week is the gold Kew Gardens 50p piece, an edition limited to just 1000 to celebrate the 250th anniversary of the gardens in 2009, of which only 629 sold to the public. Featuring the famous pagoda landmark from within the gardens on the reverse, the price for a single one of these is expected to reach £800 at auction this month.

My other, more recent, favourite, is the limited run of just six £5 notes soon to be put into circulation with a micro engraving of England football captain Harry Kane and the inscription World Cup Golden Boot Winner 2018 next to the image of Big Ben.

Keep your eyes peeled for one of these; they are valued at £50,000 apiece.

I’m writing this as the three-day Goodwood Revival, just up the road over the Downs, comes to a close. Along with the Festival of Speed, which takes place in mid July, there really is no better celebration of the magic of motoring. Whether you’re a petrol head pursuing performance and the acme of engineering, or a design darling marvelling at the sleek lines of the most memorable marques, these are the events that show why classic cars have been at the peak of price increases in the world of auctions and collecting over the past 20 years.

Even with a slight softening of values over the past three years or so, for the most outstanding cars coming to the rostrum the records continue to tumble. In fact, it was only last month that a new world auction record was set for a car when what is arguably the most desirable model ever made, the 1962 Ferrari 250 GTO, took $48.4 million at the Monterey sales.

Lewis Hamilton (Mercedes) may be leading Sebastian Vettel (Ferrari) in the F1 Driver’s Championship by some margin at the moment, but when it comes to collecting, nothing comes close to the Italian marque with the Prancing Horse mascot. It accounts for seven of the top ten prices for cars ever taken at auction …including ALL of the top six.