Sharapova didn't make the cover of InStyle (that's Katherine Heigl), but she got to preview her new U.S. Open earrings. Click here to see the Paloma Picasso earrings she wore at Wimbledon.

By Liza Horan

Sure she's got an endorsement deal with Tiffany & Co., but when she's in the mood for some costume jewelry, Maria Sharapova says, "I shop flea markets for it."

That's what the high-society celeb with a down-to-earth sensibility told InStyle magazine's Marion Fasel when interviewed for the August issue, which goes on sale today at newsstands.

The three-page look into "My Jewel Box" showcases some of the Russian's favorite new and vintage jewelry, including a large aquamarine gem from India that a friend had given Sharapova, who brought it to Tiffany to be fitted for a custom setting. Also featured are the Frank Gehry-designed dangly diamond earrings Sharapova will sport at the U.S. Open, which retail at Tiffany for $850.

Sharapova is quoted as saying she's been a fan of Gehry's architecture since the age of 12. "When Tiffany told me he wanted to collaborate on designing these for the U.S. Open, I was blown away," she says in the article.

Four of the six items featured bear the name of her hallowed sponsor, but the most precious one seems to be the cross she received at age four for her Baptism.

Sharapova's watch sponsor, Tag Heuer, also was represented in the article (below).