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Geology and ESG Research Analysis




Metals are part of our modern lives and we must think sustainability through a process: Extraction-Integration-Recycling.






Atomic number





terbium subgroup

Occurrence / Extraction

Present in monazite, bastnasite.  In less amounts in samarskite, gadolinite, and xenotime.

Extraction:  converted into gadolinium chloride (GdCl3) or gadolinium fluoride (GdF3). Passing an electric current through the first compound releases pure gadolinium.


Gadolinium has found some use in control rods for nuclear reactors and nuclear power plants; it is used to make garnets for microwave applications. 

Gadolinium is utilized for both its high magnetic moment (7.94uB) and in phosphors and scintillated material. When mixed with EDTA dopants, it is used as an injectable contrast agent for patients undergoing magnetic resonance imaging. With its high magnetic moment, gadolinium can reduce relaxation times and thereby enhance signal intensity.

Metallic gadolinium is rarely used as the metal itself, but its alloys are used to make magnets and electronic components such as recording heads for video recorders. It is also used for manufacturing compact disks and computer memory.

The extra stable half-full 4f electron shell with no low lying energy levels creates applications as an inert phosphor host. Gadolinium can therefore act as hosts for x-ray cassettes and in scintillated materials for computer tomography.


The metal does not tarnish in dry air but an oxide film forms in moist air. Gadolinium reacts slowly with water and dissolves in acids. Gadolinium becomes superconductive below 1083 K. It is strongly magnetic at room temperature.
Gadolinium is strongly paramagnetic at room temperature, and exhibits ferromagnetic properties below room temperature.

Gadolinium demonstrates a magnetocaloric effect whereby its temperature increases when it enters a magnetic field and decreases when it leaves the magnetic field. The effect is considerably stronger for the gadolinium alloy Gd5(Si2Ge2) [2].
It also has the highest neutron-absorbing ability of any element. A piece of gadolinium stops neutrons better than any other element.

Atomic mass: 157.25 g.mol -1
Electronegativity according to Pauling: 1.1
Density: 7.9 at 20°C
Melting point: 1311 °C
Boiling point:  3233 °C
Named after the mineral gadolinite, named for J. Gadolin, a Finnish chemist and mineralogist.

Relative abundance

The abundance of gadolinium in the Earth's surface is estimated at about 4.5 to 6.4 parts per million. That would make it one of the most abundant of the rare earth elements. It ranks above bromine and uranium, but just below lead and boron in order of abundance                                                   Gadolinite:((Ce,La,Nd,Y)2FeBe2Si2O10. Called gadolinite-(Ce) or gadolinite-(Y))

atomic mass (g.mol -1)


density (g/cm3)


Oxydation number


Melting point (°C)


Boiling point (°C)


Magnetic moment


Abundance in the Earth's crust ( ppm)



Jean Charles Galissard de Marignac (CH) in 1880