Keira Knightley's Engagement Ring: How Much It Costs!

Us Weekly

Right on, James Righton!

When choosing an engagement ring for Keira Knightley, Righton selected a stunning yet classic style. The Klaxons rocker, 28, and the Oscar-nominated actress, 27, confirmed their engagement Friday, and since then Knightley has been flaunting her new bling.

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"This is truly the most classic of all engagement ring styles," jewelry expert Michael O'Connor tells Us Weekly. "It's a solid platinum band with a brilliant cut solitaire diamond, approximately 2 carats. Estimated price tag is $40,000."

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O'Connor adds, "Not only is this ring sophisticated and timeless, but I love that she's wearing a platinum setting that you can find within most budgets."

On Sunday, the newly engaged couple packed on the PDA while going for a stroll in London -- with Knightley's diamond on full display.

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The couple have been dating for about a year before Righton popped the question. It will be the first marriage for both.

This article originally appeared on Keira Knightley's Engagement Ring: How Much It Costs!