The ‘Roar’ hitmaker, who was without her lover John Mayer, looked happy wearing the bling, Metro.co.uk reported.
However, a few hours later the ring was mysteriously gone when the 29-year-old singer partied with the Brit brigade backstage and swapped outfits in the Patron Tequila backstage bash.
Perry had earlier said that she is dating her crush, as she had a crush on Mayer for a long time and they fit great together.
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