美玉无瑕

Explanation: Flaw: jade spots. Jade is not above a little spot. A perfect metaphor or something without shortcomings. 　　Source: Yuan Wang Shih-fu, "The West Chamber" third off the third: "He is a prettily flawless jade, Fen Lian Seng Chun, shallow heap crow." 　　Examples: One is Langyuan cents Pa, one ~. ★ "Dream of Red Mansions" The fifth round