The most expensive watches in the world change on a regular basis as brand’s vie for the PR mileage that can be earned from claiming the crown for the most excess, whether it is through using precious stones of jaw-dropping sizes or the most bewildering assortment of complications.

But the most expensive watches don’t necessarily come from new stock. Patek Philippe prices at auctions, for example, can reach several million dollars. Determined interest from the Breguet Museum also saw two historic Breguet pocket watches sell for a combined total of 6.5 million Swiss francs at Christie’s sale in Geneva in 2012.

It was perhaps unsurprisingly Hublot that made marketing capital out of pitching a watch at the cool 1 million Swiss franc mark with its Big Baby 44mm Baby Million, which was soon followed by a more expensive piece, with a two-million dollar price tag and a solid-gold case, dial and bezel set with 72 baguette diamonds for around 20.85 carats.

Always one step ahead of the competition, Hublot presented its five-million dollar Big Bang at BaselWorld 2012. Yes, five million dollars! It has to be one of the most expensive watches in the world. Its case is set with 1282 hand-picked diamonds from around the world, for a total of over 100 carats of baguette diamonds (which, incidentally, represents half a per cent of the annual production of Botswana, the world’s biggest diamond producer). It’s little wonder that it is one of the most expensive watches, but for that price you don’t event get a tourbillon! Just a self-winding mechanical movement.

For the most expensive watch with complications, Franck Muller’s Aeternitas Mega 4 is hard to beat. This watch features a staggering 36 different complications and costs a cool 2.6 million Swiss francs. In addition to its tourbillon movement, the Aeternitas Mega 4 features a complicated striking mechanism that can sound the hours and the quarter hours automatically, or the hours, quarters and minutes. On top of that there is a perpetual secular calendar that indicates the day, date, month, moon phase and leap years and runs for an impressive cycle of 1,000 years (most perpetual calendars can operate without adjustment “only” until the year 2100).

In addition to the date, day of the week, month, 24-hour day and night indication and leap-year cycle, this high-end timepiece also displays the equation of time. The dial of the watch, which looks bewildering at first glance, is completed by power displays for the movement and the chimes, as well as two separate sub-dials that can be programmed to display different time zones.

In summary, the most precious stones, the most complicated complications or an historical rarity beyond parallel are what is required to make the most expensive watches!

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