It’s not that long ago that I wrote about some of the stranger items that come up for auction. They tend to be treated like religious relics, things that are not necessarily attractive or valuable in themselves, but take on huge significance because of whom they once belonged to.

Another of the more bizarre examples has just surfaced: Edward VIII’s wisdom tooth. Described as “stained” – presumably as result of his smoking habit – the tooth was removed in 1940, four years after the king abdicated and went into exile as the Duke of Windsor. Kept by the dentist’s family, it is now expected to fetch £10,000 at auction.

Who would want such a thing? You’d be surprised; wealthy and ultra-keen royal watchers, for instance, are just the sort to have something like this mounted and put in a glass paperweight.

Never underestimate the attraction of items that many of us would find bizarre and off-putting as collectables: anything Elvis, for instance, from his hair to his nail clippings, can find an audience. Unlike other collectables, the only thing that makes them valuable and desirable is their association with an historic figure. On every other count, from condition to aesthetic appeal, they score zero on the appeal scale, but that doesn’t matter to the aficionado of such things.

Occasionally, a game-changing moment can happen for an area of collecting. One such happened ten years ago when a collector in Chicago published an internet blog about an unknown American street photographer named Vivian Maier, who had died that year.

The reaction was viral and Maier’s genius at last emerged from the shadows.

Born in 1926, Maier never married and worked much of her life as a nanny. In 1952, she bought her first Rolleiflex camera, and thus started a remarkable amateur career during which she took hundreds of thousands of street photographs, self-portraits and other subjects that have now been recognised as being on a par with the work of the leading American photographic artists of the 20^th century, like Diane Arbus, Robert Frank and Helen Levitt.

Maier’s work, now published in a series of books, resides in major public and private collections, with several documentaries on her committed to film.

This has naturally done wonders for the value of prints and plates of her images, but it has also attracted huge numbers of people to the field of street photography and vernacular photography – anonymous everyday scenes of life from yesteryear – which has become a buzzing market at auction, at fairs and dealing online.

It’s not often that you can pin down the beginnings of something big to such a precise date, but that 2009 blog was certainly the catalyst here.

Working as a valuer can be a bit like working as a detective. While most things consigned for auction are instantly recognisable, others are not, and if there’s no paperwork to go with them, you have to rely on your knowledge and wits.

Most of you will have witnessed how experts start to go about deciphering the unknown from watching the Antiques Roadshow. The first thing they will do is look at the item to see if it has/had any apparent function. What is it made from? Are there any identifying marks, as there so often are with porcelain and silver, for instance? Is there a maker’s label? Is there any documentation, no matter how flimsy, that comes with it? Finally, how did it come to be in the consignor’s hands?

Piecing the story together is one of the most fascinating aspects of working in this wonderful business of ours. It can be frustrating but never boring. Sometimes, when you have unpacked all the clues, you find you have a real treasure in your hands.

No matter how long you work as a valuer and auctioneer, there is always another surprise around the corner. The latest was a strange brass instrument with a turning handle identified by a colleague at another auction house as a tobacco shredder.

One of the most successful and interesting dealers and collectors of modern times is the American Warner Dailey. Now in his seventies, he came to England in the early 1970s. His most important client was the businessman and philanthropist Malcom Forbes.

Warner has a never ending list of stories about his experiences, the common theme of which is the fact that he has always been entirely immersed in his passion for what and why people collect.

He started as 17-year-old, clearing out the attic of a wealthy family who lived nearby in Upstate New York. They went by the name Pierpont Morgan and his success in selling their cast-offs made them take notice of this precocious teenager. However, it was his canny foresight in appreciating the future collectable attraction of New England quilts that also set him on the road to riches. Touring round in a beaten up old car in the run-up to Halloween, he would offer 50 cents and a new blanket to protect the precious pumpkins from frost to any householder who would hand over their disregarded hand-stitched quilt covering the vegetable plot.

Warner made a small fortune as a result, but he would never have spotted the opportunity if had not been for his early and enduring passion for the art and craft of his fellow countrymen.