Jeweler Lorraine Schwartz said the ring on the "Crazy in Love" singer's finger during an appearance at Radio City Music Hall was worth more than $5 million, People magazine reported Saturday.
Knowles, 27, and rap mogul Jay-Z, full name Shawn Carter, have yet to publicly confirm reports they are married.
Knowles' sister, Solange, referred to Carter as her brother-in-law during a recent interview.
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