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Lady Gaga Accepts Heart-Shaped Engagement Diamond On Valentine's Day; Ring's Value Estimated To Be $500K

Lady Gaga surprised her 5.6 million Instagram followers on Monday with the announcement of her Valentine’s Day engagement to actor Taylor Kinney and a peek at her unusual heart-shaped diamond.

The 28-year-old six-time Grammy winner posted a close-up of her new engagement ring featuring what’s estimated to be an 8-carat heart-shaped center stone. Her caption read, “He gave me his heart on Valentines’s Day, and I said YES!”

Kinney, 33, who is most famous for his role as Lieutenant Kelly Severide in the TV shows Chicago Fire and Chicago P.D., posted a sweet photo of himself and his famous fiancée, along with the caption, “She said YES on Valentine’s Day.”

Depending on the stone’s quality, the ring could be worth upwards of $500,000, according to a report by HollywoodLife.com.

Jewelry expert Shari Fabrikant of Robert Fabrikant Inc., who is often called on to value celebrity engagement rings, told HollywoodLife.com that the heart-shaped center stone appears to be about 8 carats in size and of very fine quality.

“The setting is simple with a few round diamonds down the side,” she said. “If the stone is an E color and VS1, it would run close to $500,000. It’s a really special stone. It’s extremely difficult to get large heart shapes. It’s very unique for a ring.”

The chart-topping diva, who has never been shy about pushing the boundaries of fashion (she famously wore a dress made of flank steak to the 2010 MTV Video Music Awards), had hinted to Howard Stern in a recent interview that Kinney could be the one.

The couple first met on the set of the music video for Gaga’s 2011 song “You & I,” in which Kinney played her love interest. They started dating several months later and then broke up for a brief time in May 2012. One month later, they were back together and have been a couple ever since. No wedding plans were announced.

Photos: Instagram/LadyGaga, Instagram/TaylorKinney, Getty Images.