Sharon Stone, 58, Is Sexy and Makeup-Free in a String Bikini -- See the Pic!

Sharon Stone is doing summer right.

The 58-year-old actress beat the heat on Sunday by hitting the pool in a skimpy string bikini and without a stitch of makeup. "It's so hot today! #summer16 #staycool," she captioned the Instagram pic.

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Last year, Stone posed nude for Harper's Bazaar and opened up about being so comfortable in her own skin. "I'm aware that my a** looks like a bag of flapjacks but I'm not trying to be the best-looking broad in the world," she quipped. "At a certain point you start asking yourself, 'What really is sexy?' It's not just the elevation of your boobs. It's being present and having fun and liking yourself enough to like the person that’s with you."

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Stone added, "If I believed that sexy was trying to be who I was when I did Basic Instinct [in 1992], then we'd all be having a hard day today."