The Antiques Roadshow has been running in the U.K. since 1979 and in the U.S. since 1997. It's a simple idea: Get together a group of antique experts, put up some tables, set up the cameras and invite the public to come in and have their items valued by the experts. People bring all sorts of things, from paintings to jewelry and silverware.

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And the valuations? Usually, you are talking hundreds or thousands of dollars. But sometimes, just sometimes, people roll up with a painting that has been gathering dust in the attic or a collection of sports memorabilia and are astonished and pleased to find out that it comes in at six figures (or more). Here are 10 of the most expensive Antique Roadshow finds of the decade.

Joseph Kleitsch Oil Painting - Valued At $500,000

When you live in New York City, you are accustomed to things coming at you out of the blue. But nothing could have prepared this picture's owner for the news she received in 2014. The appraiser put a $500,000 price tag on the painting. The owner was, of course, thrilled.

Joseph Kleitsch was an American-Hungarian portrait and Plein air painter who moved to Laguna Beach, California in 1920. He was an important Impressionistic artist of his time. While not so familiar to some today, he is still very well regarded in artistic circles.

Banksy's Mobile Lovers - Sold For $526,000

Banksy is an English street artist and political activist. The only thing is, nobody is quite sure who he is. He tries to maintain strict anonymity. His art can be found on walls and the sides of buildings just about anywhere in the world.

Mobile Lovers (mobiles are cell phones in England), shows a man and a woman embracing while checking their cell phones. It's very Banksy. The painting was on a door across the street from a Boys' Club in Bristol, England. When it showed up on the English Antiques Roadshow in 2014 and was valued at over $500,000, the Bristol City Council waded in, claiming ownership. Banksy countered, sending the Boys' Club a signed letter saying it was theirs. The Club sold it at auction for around $526,000.

1896 Frederic Remington Portrait - Valued At $600,000 -$800,000

An Alabama man brought a portrait of his great-grandfather, Lea Febiger, to the 2014 Antiques Roadshow event in Birmingham. It seems that Febiger and the noted artist had been friends. The painting's owner even had a letter from the artist to his great-grandfather. That means the painting had great provenance, a kind of guarantee of authenticity.

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It came as a very pleasant surprise to the man that the picture was worth $600,000 to $800,000. No word on what became of the painting after the valuation. Often owners vow never to part with a treasured item, then think better of it and sell at auction.

Barbara Hepworth Sculpture - Valued At $981,000

When Antiques Roadshow hit Cornwall in 2012, a school librarian showed up with a Barbara Hepworth bronze sculpture. She had no idea what it was worth, but she did know that Hepworth had donated the piece to St. Ives school in Cornwall, Southwest England before her death in 1975.

She told the tale of how the piece had sat on the head teacher's desk, doing duty as a paperweight. She was, as the English say "gobsmacked" (surprised) to learn that it was worth $981,000. The bad news is that the school could not even afford the insurance premium on the piece. The good news is that it went to a museum and is now on display. The headteacher commented that is was the most expensive paperweight ever.

1904 Diego Rivera El Albanil Oil Painting - Valued At $1 Million

When a man showed up at the Corpus Christi, Texas event in 2012, he had no idea what he had on his hands. He knew he liked the painting, and just wondered what it was worth. It turns out that it was painted by Rivera, a well-respected Mexican painter in the early 20th century.

An "albanil" is simply a construction worker. In the painting, the man is holding a shovel and wearing a poncho and broad-brimmed straw hat. Mexicans love Rivera and will pay prices high for his work. It's worth? Up to $1 million. Since this valuation was in 2012, we're betting it's gone up in value.

Boston Red Stockings Sports Memorabilia - Valued At $1 Million

This happy woman who brought the cache of Boston Red Stocking memorabilia into an Antiques Roadshow stop in New York in 2014 was the great-great-granddaughter of the woman who ran the boarding house in Boston where the team had stayed in 1871. The result was that great-great-grandmother ended up with a bumper crop of vintage baseball cards and other items, which had been passed down the family.

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The value? $1 million. The Boston Red Stockings were formed in 1871. Over the years, the team underwent name changes and a relocation or two. They are now in Atlanta and known as the Braves.

Fabergé Japonica Flower In Vase - Valued At $1.27 Million

Back in England, we come to our first million-plus item. It's a Fabergé Japonica flower made from gold, pearls, lapis, and rock crystals. It is around four inches tall. The crafted flowers sit in a crystal vase, in which rock crystal simulates the appearance of water.

Fabergé was the iconic French jeweler, who created stunning items for royalty and the rich and famous during the early 20th century.  Faberge flowers are rare and command premium prices. But, unbelievably, it seems that the owners of the piece just stashed it under a bed. We bet that changed after the $1.27 million valuation.

F.A. Cup - Valued At $1.3 Million

Retired from service in 1992, this silver cup had been held high by winning teams in the Football Association's annual knock-out football (soccer) championship since 1911. The F.A. is now on its third silver cup because getting tossed around by winning teams inflicts a lot of wear and tear.

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In 2005, it was purchased at auction for around $600,000 and then donated to the National Football Museum. By the time it got to the Antiques Roadshow in 2016, it had more than doubled in value at $1.3 million.

Chinese Rhinoceros Horned Cups - Valued At $1 Million - $1.5 Million

A collector came into the Antiques Roadshow when it stopped in Tulsa, Oklahoma in 2011 to have his Rhinoceros horned cup collection valued. Carved from rhinoceros horns around 1700 the cups that are used as drinking vessels.

Believe it or not, the man had paid a mere $5,000 for the whole set. Imagine how pleased he was to learn the set was worth between $1 million and $1.5 million.

Patek Philippe Pocket Watch - $2 Million - $3 million

You can expect to pay tens of thousands of dollars for a new Patek Philippe watch. The luxury Swiss watchmaker has a reputation for crafting beautiful watches with intricate movements. But what about a 1914 Patek Philippe watch? It depends on the condition. The pocket watch brought in to the Antiques Roadshow in St. Paul, Minnesota was in near perfect condition.

As of 2016, the watch was valued at $1.5 million. Now? A whopping $2 million to $3 million.

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