PICTURE: See Louise Roe's Engagement Ring!

USMagazine, Thursday, December 6, 2012, 4:00pm (PST)

Louise has a whole lotta bling!

Announcing her engagement to her Abercrombie & Fitch model boyfriend of two and a half years, Josh Slack, Dec. 5, Fashion Star host Louise Roe proudly showed off her new engagement bling via Twitter.

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"I was given my great-grandmother's aquamarine ring, I love!" the 31-year-old tweeted along with a picture in which she is modeling the ring while hugging Slack, 24.

Though Slack got down on one knee with the family heirloom, he and Roe intend to choose a new ring together later in their engagement.

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Speaking to England's Fabulous magazine in July, Roe -- who hosted the CW's short-lived makeover series Plain Jane -- said she was anxious to walk down the aisle and start a family. "Lots of my friends are getting engaged -- they're dropping like flies!" she told the magazine. "My two older sisters are mummies and I'd love kids running around one day, too."

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Prior to replacing Elle Macpherson on Fashion Star, Roe was best known in the U.S. for appearing on season 2 of MTV's The City alongside Olivia Palermo, Whitney Port, Erin Kaplan and Roxy Olin.

This article originally appeared on Usmagazine.com: PICTURE: See Louise Roe's Engagement Ring!