books.google.com - In the great barranca known today as Copper Canyon, the small mining town of Batopilas once experienced a silver bonanza among the largest ever known. American investors, believing that Mexico offered an unexploited cornucopia, began purchasing mines in the Sierra Madre, seeking to expand their hold...http://books.google.com/books/about/The_Silver_of_the_Sierra_Madre.html?id=f34NYnGHl1QC&utm_source=gb-gplus-shareThe Silver of the Sierra Madre
