Bonanza, MissouriBonanza is an extinct hamlet in central Caldwell County, in the U.S. state of Missouri.HistoryA post office called Bonanza was established in November 2nd, 1881, by Manford F. Kern, and remained in operation until October 31st, 1903. Bonanza is a name derived from the Spanish language.GeographyThe town was settled along Shoal Creek and just southwest of its former location is Bonanza Conservation Area.