Gadolinium is a silvery-white metal with high neutron capture capability, used in MRI contrast agents.
Core Principles & Analysis
Jean Charles Galissard de Marignac identified gadolinium spectroscopically in 1880, and it is named for the mineral gadolinite honoring chemist Johan Gadolin.
It has the highest thermal-neutron capture cross-section of any stable element and is ferromagnetic just below room temperature.
Gadolinium chelates are the standard contrast agents for MRI scans, and the element serves as a neutron absorber in reactors.