Over the years 1825–1849, Frédéric Chopin wrote at least 59 Mazurkas for piano, based on the traditional Polish dance: 58 have been published 45 during Chopin's lifetime, of which 41 have opus numbers 13 posthumously, of which 8 have posthumous opus numbers 11 further mazurkas are known whose manuscripts are either in private hands or untraced. Wikipedia