Katy Perry, whose hair is now a plucky shade of purple, showed up to the NARM Artist of the Year Awards in California wearing a sheer, black striped dress that looked suspiciously familar.

Her gal pal Rihanna hosted a New Year's Eve party in Las Vegas on December 31, 2010, wearing a very similar dress - only hers was red.

Katy wore Louboutin shoes and rosary beads to complete her look, while a then-red-haired Rihanna opted for a chunky necklace.

The two pop stars have been friends for quite some time. Rihanna even attended Katy's bachelorette party two years ago. So it's no surprise they share the same taste in clothing.

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