Kanye bought $8 million ring for Kim: expert

Andrew Innerarity/REUTERS

Kanye West's union with Kim Kardashian is a match made in prenup lawyers' heaven. But oddsmakers and some celeb watchers don't expect it to last long.

Maybe the third time's the charm.

Kim Kardashian will walk down the aisle yet again, thanks to a giant diamond valued by one expert at $8 million and Kanye West's Jumbrotron proposal Monday night at San Francisco's AT&T Park.

But if history is any lesson, she might not wear that bling for long.

Online bookmaker Paddy Power puts the odds on Kimye's marriage lasting less than two years at 2-1. That might be due to the fact her first marriage, to record producer Damon Thomas, lasted four years, and her second, to former Brooklyn Net Kris Humphries, wrapped up in a mere 72 days.

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Her ex-father-in-law, William Humphries, isn't wagering on a lengthy union, either.

'Does a leopard really change its spots? I don't think so,' the NBA dad tells the Daily News. 'Not much changes. It's just different actors this time around.'

If this love story reaches the same tragic conclusion for the new parents, West, 36, and Kardashian, who turned 33 on the day of her engagement, better have their paperwork in order. We ain't saying she's a gold digger, but per West's famous song, lawyers are saying, 'We want prenup, we want prenup.'

'This is not the mother of all prenups, but it's going to have to be pretty close,' says celebrity divorce lawyer Raoul Felder, who managed the splits of former Mayor Rudy Giuliani and Martin Scorsese. 'They both have careers that could become more valuable, and each one could claim the other one helped their career.'

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Madison Avenue's so-called Duke of Divorce likens the power couple's union to the merging of two companies. Drawing up their prenup could take weeks and rack up $100,000 in legal fees.

Unlike Kardashian's last marriage, she's not the breadwinner this time. She's worth $40 million to Kanye's $100 million. That means it's the groom who must cover his assets.

Robert S. Cohen, who represented Christie Brinkley and Ivana Trump in their divorces, says they shouldn't be financially bound to each other if the Wests go south.

'They should be able to walk away without any obligation to the other, except to the extent that they do projects together, and then the prenup should deal with splitting that 50/50,' he says.

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But what about that ring?

When Kardashian and Humphries split, the hoopster put the 20.5-carat emerald-cut Lorraine Schwartz rock - which reportedly retailed for $2 million - on the auction block at Christie's, where it sold for a paltry $749,000.

While it may seem that Humphries gave her the bigger rock, Kanye proposed with a perfect, D flawless cushion cut diamond and worked with famed jeweler Lorraine Schwartz on the ring. According to Forevermark Diamond expert Adelaide Polk-Bauman, such a ring would set West back $7 million to $8 million. 'This is exceptionally rare. Very few places in the world have diamonds such as that.'

Kanye had a big diamond in mind for the proposal as well.

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While Humphries laid out rose petals and candles in Kim's home for an intimate - at least by Kardashian standards - engagement (it was televised, after all), West took her out to the ballpark with a 50-piece orchestra on deck.

Renting AT&T Field alone starts at $220,000, with $200,000 covering field access and the rest paying for use of the HD scoreboard, cameras and technical crews.

That's not counting the musicians who serenaded the lovebirds from the outfield.

The orchestra was assembled in just two days, according to a violinist who spoke on condition of anonymity after signing two nondisclosure agreements about the primo gig. That left them little time to master the songs selected by West to set the mood: His own 'Knock You Down' and Kim's favorite - Lana Del Rey's 'Young and Beautiful.'

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'We found out in the morning what the music would be, and only got to practice together [Monday] night, for less than an hour,' the musician tells the Daily News.

Of course, cameras were keeping up with Kardashian and her beau the entire time, as fireworks lit the sky above a small crowd of movers and shakers, including Silicon Valley billionaires, Kardashian bestie Jonathan Cheban and 'Girls Gone Wild' Lothario Joe Francis.

Francis told the Daily News it was like a 'military operation.'

'She was so beautiful, and people gasped when he got down on one knee,' said Francis, who was sitting 200 yards away. 'I believe Kanye is a genius, I do. He got all these high-profile people to San Francisco, to hotels and moved them all around without anyone tweeting sightings. We were all sworn to radio silence.'

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The couple's 4-month-old daughter, North West, did not attend due to the Northern California chill, but Kardashian's mom, Kris Jenner, and sisters Kourtney, Khloe, Kylie and Kendall were on hand.

'I think Kim thought her sisters were abandoning her on her birthday,' Francis related. 'They said they were at a spa in Arizona, and they were fake Instagraming.'

For a glamorous couple who jet-set the world clad in the finest designer threads (Kim chose Valentino on engagement night), the baseball stadium proposal actually seemed down to earth, say some Kimye fans.

'That's very beautiful and thoughtful, and he stepped up in a very human way,' says SoHo resident Eileen Esposito, 28, who describes herself as 'ready to get proposed to.' 'A Jumbotron is more normal. It's not like a superstar thing.'

But other fans of the 'Gold Digger' emcee were left wanting.

'If Kanye was proposing to me, I'd want something bigger,' says Laura Stern, 25, of the East Village.

With Lauren Holter