The value of Brazilian quartz to the allied war effort is shown as narration proclaims "two-way radio is the one really new instrument in the armory of warfare." Explains the value of quartz in radio communication, showing how a wafer of its crystal makes possible the simultaneous broadcasting of many stations without overlapping. The film emphasizes the necessity for international cooperation in the war effort. Shows quartz mining in Brazil: pictures the hard manual labor involved in mining Brazilian quartz, the inspection, the exportation of most of it to the United States, and the laboratory cutting of it to fit the complex instruments of World War II. Personages: President Roosevelt, Brazilian President Vargas, Joseph Stalin, General Marshall, and Madame Chiang Kai-shek (see U.S. National Archives and Records Administration catalog record http://research.archives.gov/description/40254).