Kim Kardashian wore a Valentino ensemble that cost $6,800 on Monday night when rapper Kanye West proposed to her on her 33rd birthday.

The reality star was all smiles in a lilac and white number as she accepted the marriage proposal in front of friends and family at the AT&T stadium rented out for the occasion in San Francisco. Her mother, Kris Jenner, was on hand as well as her best friend Jonathan Cheban.

Kardashian's gown was covered in delicate beadwork and hugged her post-baby body, yet remained demure with a high neckline, long sleeves and above the knee length.

West gave his fiancee a Lorraine Schwartz diamond ring worth an estimated $1.6 million.

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Kardashian's dress is part of Valentino's fall 2013 line and it is not yet available online. She may have seen the gown when she and West attended Valentino's show at Paris Fashion Week earlier this year. The dress was previously worn by Charlotte Ronson at the Brazil Foundation Gala in New York City, who dressed up the look with black platform pumps and an ivory box clutch.

French actress Lea Seydoux wore it with silver Jimmy Choos at the Cannes Film Festival while promoting Blue Is The Warmest Colour, according to Daily Mail.

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West hired a 50-piece orchestra and on the giant stadium screen, the proud dad of baby North West posted, "PLEEEASE MARRY MEEE!!!" while an band played Lana Del Ray's Young and Beautiful followed by the rapper's collaboration with Ne-Yo and Keri Hilson, Knock You Down.

Tags: Kim Kardashian