Amal Clooney, $750,000
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The infamous bachelor George Clooney finally decided to settle down when he proposed to Amal Alamuddin in April 2014 with an “ethically-mined” 7-carat emerald-cut diamond based on a platinum setting with “tapered baguette accents.” Some experts place the cost of the ring at around $600,000 – $750,000.