Now that Kim Kardashian has moved on with a new man and new baby, her ex-husband Kris Humphries has reportedly decided to auction off the diamond engagement he gave to the reality star years ago. 

After only being married to Humphries for 72 days, Kardashian filed for divorce on October 31, 2011. The Celtics player has allegedly made plans to sell the ring at an upcoming Christie's auction titled "Bright & Beautiful" in New York, according to reports. 

The auction is set to take place on Oct. 15. He has yet to admit to selling the 16.21 carat Lorraine Schwartz ring, which is expected to sell between $300,000 and $500,000. Humphries reportedly paid nearly $2 million for the ring. 

Radar Online reported that Humphries was very upset when the divorce went down. 

"On the day the divorce was finalized, Kris was somber and a bit sad," a source told the site. "There was absolutely no celebration, or parties. It was the end of his marriage, and it was a reflective time for him. It didn't surprise him that Kim carried on the way she did on the show."

As reported earlier, Humphries' aunt and uncle Dedria and Mike were among the 36 Humphries family members who traveled across the U.S. to attend the athlete's wedding to Kardashian in Santa Barbara, Calif., which the couple followed with a lavish honeymoon in Italy.

"It was a sham," Dedria said. "My understanding of marriage is people are going to give it more than 72 days unless there's serious abuse. If I felt somebody had duped me and used me in front of the whole world, I would be very angry."

Kardashian gave birth to baby North West on June 15 and is currently dating Kanye West.