Logan's dialogue here is taken from L. Frank Baum's description of Ozma after she is transformed into a girl at the end of Marvelous Land of Oz.

"and from the couch arose the form of a young girl,
fresh and beautiful as a May morning. Her eyes
sparkled as two diamonds, and her lips were tinted
like a tourmaline."

The Oz books are, of course, nonfiction and this is almost definitely how Dorothy described Ozma to Baum when he was doing research for the book.