Sex sells ... pretty much anything, including watches. Believe it or not, there's a collectible market for sex-filled timepieces, both old and new. They're called "erotic" watches, or what some might call "pocket porn."
These timepieces are definitely not for the faint of heart.
"Erotica has been a very important part of watchmaking history from when we first started with pocket watches," Chris Del Gatto, consultant to high-end jeweler Jacob & Co., tells CNBC. "In the beginning, people would commission pocket watches with faces of their wives or lovers because oftentimes people were separated for months or years at a time."
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Unless you're a serious watch collector, you probably haven't heard of these titillating timepieces. Hand-painted and very detailed (oftentimes extremely graphic) images are hidden behind dials in watches.
For centuries, portable porn has been carried around discreetly, but with a simple twist of a knob, an original erotic scene was revealed. And this "pricey porn" only gets more expensive with age.
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In March 2011, a dentist and self-proclaimed "erotica artifact collector" auctioned off more than 33 erotic watches and animated objects in Switzerland. Twenty-six of those objects were watches that sold for more than a total $750,000.
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The auction house, Antiquorum Auctioneers, says "about 90 percent was sold to Chinese collectors over the phone or the Internet." One Chinese bidder couldn't get enough, taking home 10 triple-X watches.
The highlight of the Swiss dentist's erotic collection? A rare 18-karat gold, enameled pocket watch from 1810 with a concealed, animated erotic scene that sold for more than $220,000.
But "pocket porn" comes in all shapes and sizes. Modern-day versions like the "Caligula" diamond watch from Jacob & Co. sound a little scary as it shares the name of sex-crazed and violent Roman Emperor Caligula. But this "blinged-out" version is the present-day answer for the super-rich watch collector who doesn't mind a supersized price tag of $1,600,000.
Covered in pave, triangle-shaped diamonds—the Caligula diamond watch is a one-of-a-kind piece that reveals an animated erotic scene behind the diamond dial.
But, if you're not willing to spend a small fortune on an erotic watch, you can purchase the "regular" Caligula watch that simply comes in rose or yellow gold for just $69,000. And yes, the company is serious when it tells us there are only 69 pieces being commissioned.
"We have people come in [to buy the watch] who want their wives, who want their girlfriends," says Del Gatto. "We're the only brand I know of that's doing that today."
—By CNBC's Erica Emmich. Follow her on Twitter and Instagram: @MegaMoneyGal.
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