Discovered : 1949 by S.G. Thompson and co-workers Isolated in Berkeley, California, USA Origin : The element is named after the place where it was discovered. Description : A radioactive, silvery metal obtained from plutonium in nuclear reactors. Less than a gramme is made each year. Image : Echoes of 1969. Berkelium animation - click the icon above to launch. (Quicktime required) For more 109 Project animations click here. Berkelium mousemats are available for purchase - Click the product icon for more information and pricing.