Crystal Harris is auctioning off her $90,000 engagement ring from Hugh Hefner.
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According to the listing on Christie's, it's expected to sell for $20,000 to $30,000. The 3.39-carat circular-cut diamond will hit the auction block next month.
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The former Playboy model called off her wedding to Hefner in June. Lifetime was due to air a special Marrying Hef, which was briefly canceled.
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But instead, the network changed the special to Runaway Bride.
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Hefner opened up about his sex life with Harris in The Hollywood Reporter earlier this month.
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"We had sex once a week. We had sex with her and a girlfriend. We had sex the first night that we met, with another girl, and it was such a nice relationship that I kept them both over for a weekend," he said.