Gilman Hall - Where Plutonium Was Identified

Photo: Gabriel Classon (gabeclasson on Flickr), CC BY 2.0 (cropped)

A stop on UC Berkeley Campus Walk, a free self-guided tour.

This modest chemistry building does not look famous, but a small room upstairs changed the 20th century. On February 23, 1941, in Room 307, chemist Glenn Seaborg and his colleagues identified a new element, number 94: plutonium. Their tiny sample had been made in the cyclotron built by Berkeley physicist Ernest Lawrence. The discovery was kept secret until after World War II, because plutonium became a key material of the Manhattan Project.

Room 307 is a National Historic Landmark, and the building is honored by chemists for research that led to two Nobel Prizes in Chemistry: William Giauque's in 1949 and the 1951 prize shared by Seaborg and Edwin McMillan.

Plutonium was only the start. Berkeley scientists went on to discover more heavy elements, including berkelium in 1949 and californium in 1950, named for the city and state you are standing in. Element 106 was later named seaborgium, for Seaborg himself.

The building is used for classes and labs, so admire it from outside.

Getting here: Walk southeast about 200 meters from the Mining Building into the College of Chemistry complex.

Did you know?: Seaborgium was the first element named for a living person; Seaborg was still alive when the name was adopted.

Photo op: Frame the building's entrance from the plaza and imagine the wartime lab work going on upstairs.

More on Wikipedia: Gilman Hall · Glenn T. Seaborg · Plutonium · Berkelium

Gilman Hall - Where Plutonium Was Identified

Stops on this tour