The secret lab where a $2.6 million watch was made

Erica Wright | CNBC

Patek Philippe likes to keep things quiet. The family-run, 175-year-old watchmaker creates some of the most sought-after, expensive, and most collected watches in the world, but they rarely do much publicity. And they never allow cameras into their highly secure watchmaking lab in Geneva.

Until now.

In a rare look inside the hyper-exclusive world of Swiss watchmaking, Patek Philippe allowed "Secret Lives of the Super Rich" to video the making of Patek's most expensive watch ever—the $2.6 million Grandmaster Chime.

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The watch, made to honor the company's 175th anniversary, is the most complex that Patek has ever built. It's got 20 complications—including a grande and petite sonnerie, a minute repeater, an instantaneous perpetual calendar with a four-digit year display and a second time zone. It's also got two patented global debuts in the domain of chiming watches: an acoustic alarm that strikes the alarm time and a date repeater that sounds the date on demand.

Patek Philippe’s $2.6 million Grandmaster Chime
Source: Patek Philippe

The coolest feature: It's the company's first double-face wristwatch, so the face flips from the time and sonnerie to the other face, which displays the perpetual calendar.

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Each of the tiny pieces are handmade and measured in micrometers. All told, there are 1,300 parts, and it took seven years and more than 100,00 hours just to develop the movement inside the watch. And it is painstaking work to create a watch like this. Everyone working in the lab wears lab coats, booties and face masks to prevent even a single spec of dust from entering the watches.

But even if you have the $2.6 million to spend, don't count on getting one. Patek is only making seven pieces, and it requires prospective buyers to apply first—and then they only choose the most discerning buyers.

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Watch "Secret Lives of the Super Rich" on Tuesday, March 24, at 10 p.m. ET/PT.