Eavesdrop on a conversation between a group of watch collectors, and you could easily be forgiven for thinking they were chattering in code. In effect, they often are, spouting arcane reference numbers such as 5711, 2499, 6263, 1665, 6542 and 1518, and looking askance at any novice ignorant enough to not instantly recognise the iconic timepieces that carry these deeply unsexy numerical callsigns. If you want to be conversant in watch nerd circles, you’ll need to wrap your head around the numbers first.

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Almost every watch collector you meet will have at least one horror story of unwittingly having purchased a monstrous timepiece comprising components cobbled together from all manner of sources, known as a “frankenwatch”. Perhaps worse, they’ll have been passed off a total phony—sophisticated counterfeits can be incredibly difficult to detect these days. To guard against these tragic events, buy new from a brand boutique or authorised dealer, or purchase from a reputable second-hand source you’re highly confident you can trust—and to whom you can return, should problems arise.

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Watch collectors have much the same mindset (and in many cases, similarly awkward social skills) as the average aficionado of vintage Star Wars figures. They simply have a great deal more money to indulge their acquisitive urges. Just as the value of an original 1978 vinyl cape Jawa figure is greatly increased if this rarity remains within a mintcondition Kenner Toys package, so too will most watches’ prices be higher and provenance easier to verify if sold complete with the original box, receipts and authenticity papers.

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Back away from vintage timepieces that have been restored to a suspiciously shiny, scratch-free state, and certainly never submit your own classic watches to an overzealous buffing, which can throw off the overall shape. Polished cases and reconditioned dials almost always adversely affect a watch’s value. You’re looking for patina—the subtle signs of age that say a watch has history. The dinged case, faded dial and bezel with funky brown or purple hues (known as a “tropical” effect) of an old Rolex GMT lend the watch the charm of an elegant Italian gentleman of a certain vintage. The super-polished vintage timepiece, meanwhile, is like a geriatric lothario with facelifts who dyes his hair black—pitiful, really, and not fooling anyone.

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Rarity is paramount in watch collecting. This means that when 500 pieces of a particular watch were produced in yellow gold and just 50 were made in stainless steel, the latter, non-precious pieces will generally end up fetching higher prices than their blinged-out brethren. Intrinsic value be damned! Similarly, because 20th-century steel “tool watches” were designed for use and abuse by professional divers, soldiers, engineers and such, many didn’t survive. Thus, they’ve become even scarcer and more valuable, despite their workaday origins and lack of precious metals.

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The best watches are works of art, so you should purchase them as you would artworks, acquiring the things you love looking at, that you’ll find it a joy to live with each day. Collecting luxury horology as an investment is fraught with risk—some of the most expensive watches depreciate drastically the moment you walk out of the store. Conversely, certain watches that were extremely unpopular when first released have gone on to provide incredible ROI. (Famously, dealers in the 1970s struggled to find buyers for the now immensely collectible Rolex Daytona Paul Newman, with consumers back then finding its “exotic” dial weird.) The most passionate, authentic collectors don’t look for safe, solid investments. They buy what they like.

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The owner of photography specialist Hamiltons Gallery in London, Tim Jefferies, once advised me that when collecting photography, you shouldn’t try to find the next Helmut Newton or the next Irving Penn—you should just buy works by Newton and Penn. Equally, as you begin your watch collecting odyssey, don’t look for something like the Holy Trinity of Audemars Piguet, Vacheron Constantin and Patek Philippe, or The Crown ruler, Rolex. Just bite the bullet and buy those blue-chip brands.

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