The $10 gold eagle coin, named for the national bird depicted on its reverse, was created in 1795 to be the foundation of America's federal monetary system. Used primarily in international and large-scale transactions-or melted for its gold content-in its own time, today the gold eagle entices collectors with its beauty, value, and colorful history, from gold rushes and the 1933 "bank holiday" to sunken treasures and the collections of a king. Author...