Purists prefer Patek Philippe, says Vanessa Herrera, deputydirector for Sotheby's Asia watch department. Every time the auction house has a Patek in its lot, it is flagged as an auction highlight. For the Oct. 6 Sotheby's watch auction, a Patek Philippe platinum 5078P sold for 2.42 million Hong Kong dollars (US$311,000). It was 'a most sought-after piece,' says Ms. Herrera.

The seemingly simple watch, a new timepiece -- not an antique -- doesn't seem much at face value, but Ms. Herrera helps us pick apart the details to explain why it is worth every penny.

Minute-repeating function: This is the watch's only 'complication' -- a term used to describe any watch feature that does something other than tell time -- but it is considered the 'ultimate complication' by connoisseurs. It consists of 342 parts, all hidden in the casing except for a small switch on the outside that activates the function, which reports the time every minute through a coded series of delicate but distinct tones. 'It's a callback to the pocket watch,' says Ms. Herrera, who adds that a crisp, well-paced and rich-toned 'ding' is one of the most difficult things to achieve in watchmaking.

Enamel dial: Unlike metal faces, which can tarnish and darken with time and humidity, an enamel dial, produced by baking under extremely high temperatures, behaves much like bone or porcelain -- it never ages. But creating a perfect (uncracked) enamel face is another delicate element of the watchmaker's art.

38-millimeter diameter: This Patek Philippe model is an evolution of an older model, which had a smaller face. In addition to looking more substantial, the larger face improves the acoustics of the minute-repeating function as well.

Brand: 'The Patek Philippe name is to watches what Bordeaux is to wines,' says Ms. Herrera. Each watch comes with the assurance that even on the secondhand market, it will retain its value. Every Patek Philippe is handmade and assembled in Geneva and comes stamped with a Geneva Seal -- a guarantee that all mechanisms meet the highest standards.

Platinum case: Platinum is the hardest of all metals to sculpt, so much so that watchmakers wear out a set of tools for every three pieces of platinum they work with.

Traditional design: Classic designs, like this Patek Philippe, are hard to imitate. 'When there are a lot of flourishes and flash, it's easier to overlook the details. But for a simple design to be this elegant takes a real aesthetic eye,' says Ms. Herrera.

Waiting list: 'This watch is currently available on the retail market, but you can't just go in and buy it,' says Ms. Herrera. The waiting list is long, which only inflates its already hefty price. 'Think of it like an Hermes Birkin bag -- only VIP customers have a shot at scoring one. Sometimes watches with waiting lists sell for higher than retail prices in an auction simply because it is so hard to purchase one.'

Amy Ma