I'm always surprised to see where buttons pop up. Recently, it was on the facebook page for my hometown of Clemson, SC.
This button was from the cadet uniform for Clemson Agricultural College, which is now Clemson University. It was found by Russ Hebert, who is also from Clemson and who found this during one of his metal detecting digs. When I told Russ I had written a novel based on stories about discarded buttons, he explained that "believe it or not, buttons are our most sought after relic. Buttons privde provenance and are easily (for the most part) identifiable."
You can find out more in my blog here, which includes a link to a video of the hunt!