Some of the defining leaps in technology in the twentieth century occurred during the Second World War, from radar to nuclear energy. Often left out of historical discussions are quartz crystals, which proved to be just as pivotal to the Allied victory-and to post-war development-as other technologies. Quartz crystals provided the U.S. military, for the first time, with reliable communication on the front lines, and then went on to become the core of some of the most basic devices of the post-war era, from watches,...