Jacob Marinsky, 87; Chemist Helped Discover Radioactive Element

Jacob A. Marinsky, 87, a chemist who helped discover the radioactive element promethium, died Sept. 1 in his Buffalo, N.Y., home after a short illness.

While working for the Manhattan Project in 1945, Marinsky and associates Lawrence Glendenin and Charles Coryell isolated promethium, element 61 on the periodic table and a byproduct of uranium fission.

Promethium salts light up in the dark with a pale blue or greenish glow because of their high radioactivity. Commercially, promethium was used in objects such as watch dials.

The three men named the element for Prometheus of Greek mythology, who stole fire from heaven for mankind.

Marinsky earned a bachelor’s degree from the University at Buffalo and a doctorate from Massachusetts Institute of Technology. He was a professor emeritus at the University at Buffalo at the time of his death.

He signed a petition against dropping the atomic bomb on Japan in 1945 and favored disarmament during the arms race.