Celeb Engagement Rings (PHOTOS); Nicole Richie $200,000 4 carat engagement ring. The TV star - who revealed her betrothal to Good Charlotte rocker Joel Madden during an appearance on 'The Late Show With David Letterman' - worked with renowned celebrity jeweller Neil Lane on the band, which sports a flawless four carat, round diamond worth $200k.

Lane told People magazine: "We designed it together. Nicole was lovely and wonderful to work with on it! She wanted a beautiful, special ring and wanted to be intimately involved in the design."

He added: "Joel just wanted her to have her dream ring."

It was on Monday (15.02.10) that Nicole, 28, confirmed she is engaged to Joel - with whom she has two children, daughter Harlow, two, and five-month-old son Sparrow.

Joel, 30, later revealed his joy with a posting on his twitter page.

He tweeted: "Yep. I'm engaged. Very happy. Yeah we've been engaged for a while so you're all kind of late on that. But Thanks for the hooplah all the same. (sic)" (c) tPC (c) WENN

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