 In 1976, Rosario's acquisition of the Fresnillo Company in Mexico helped it become the largest silver producer in the Western Hemisphere.In the late 1970s, the rapid rise of prices for all of Rosario's products resulted in spectacular profits for the company, and it became a highly visible target for larger companies searching for growth.After a takeover fight, Reininger negotiated highly rewarding terms for the merger of the company into AMAX in April 1980.