Interesting Things with JC #336: "Room 307, Gilman Hall, UC Berkley" - The first chemical identification of element 94, took place here. It was declared a National Historic Landmark in 1966 on the 25th anniversary of the discovery of plutonium. All of Gilman Hall was designated a National Historic Chemical Landmark in 1997, followed by its listing in the National Register of Historic Places in 2003.