Yttrium (Y)

Yttrium (symbol Y) is the chemical element with atomic number 39: a transition metal, solid at 0 °C, with an atomic mass of 88.906 u. Discovered in 1794 (Johan Gadolin).

Yttrium is a transition metal classed among the “rare earths.” Low-key, it is nonetheless everywhere: it lets white LEDs make their light, makes dental ceramics tough and works in lasers. It is named after a small Swedish village that lent its name to four elements.

Key facts

Atomic number: 39
Symbol: Y
French name: Yttrium
Atomic mass: 88.906 u
Molar mass: 88.906 g/mol
Family: Transition metals
Position: period 5, group 3, d-block
State at 0 °C: Solid
Melting point: 1,525.9 °C
Boiling point: 2,929.9 °C
Density: 4.47 g/cm³
Electronegativity (Pauling): 1.22
First ionization energy: 600 kJ/mol
Atomic radius: 180 pm
Electron configuration: [Kr] 4d¹ 5s²
Abundance in Earth's crust: 33 ppm (29th most abundant element)
Indicative price: 31 $/kg (order of magnitude)
Radioactive: no
Discovery: 1794, Johan Gadolin

Origin of the name

From Ytterby, a Swedish village.

What does yttrium look like?

A shiny, silvery-gray metal, fairly stable in air in bulk form but flammable as fine shavings.

Where is yttrium found?

About 33 ppm of Earth's crust, more than lead. It always accompanies the lanthanides in the same ores. Rocks brought back from the Moon by the Apollo missions are surprisingly rich in it.

Natural sources

Xenotime
Monazite
Gadolinite
Ion-adsorption clays (southern China)

How is yttrium produced?

It is separated from the other rare earths by long, costly solvent extraction processes. World output is on the order of 10,000 tonnes of oxide a year, almost entirely in China and Myanmar.

Top producers

China
Myanmar
Australia

What is yttrium used for?

Yttrium aluminium garnet (YAG) in white LEDs and lasers.
Yttria-stabilized zirconia: dental crowns, oxygen sensors.
YBCO, a superconductor that works in liquid nitrogen.
Yttrium-90 for radiotherapy of liver tumors.
Formerly: the red in CRT televisions.

In everyday life

White LED bulb or screen
Zirconia dental crown
Car oxygen (lambda) sensor

Role in living things

No known biological role. Traces are found in some vegetables, and the body contains less than a milligram.

Hazards of yttrium

Generally low toxicity, but fine dust is flammable and inhaling its compounds can irritate the lungs.

Cosmic origin

Dying stars: Made slowly in red giants (stars like the Sun at the end of their lives).

History of yttrium

In 1787, Lieutenant Carl Axel Arrhenius picked up an unusual black rock in a feldspar quarry at Ytterby, near Stockholm. In 1794, the Finn Johan Gadolin found a new “earth” (oxide) in it, yttria. Friedrich Wöhler isolated an impure metal in 1828.

Did you know?

Four elements are named after the village of Ytterby: yttrium, ytterbium, terbium and erbium.
The white light of most LEDs is actually blue light partly converted to yellow by a cerium-doped yttrium garnet.
In 1987, the superconductor YBCO became the first to work above -196 °C, the temperature of liquid nitrogen, which is far cheaper than helium.

Isotopes of yttrium

A single stable isotope, yttrium-89. Yttrium-90 is used to irradiate liver tumors from the inside.

yttrium-86: radioactive, half-life 14.7 h
yttrium-88: radioactive, half-life 107 days
yttrium-89: 100% of natural yttrium, stable
yttrium-90: radioactive, half-life 2.67 days. Microbeads injected to destroy liver tumors (radioembolization).

Related elements

Same family (transition metals): Scandium (Sc), Titanium (Ti), Vanadium (V), Chromium (Cr), Manganese (Mn), Iron (Fe), Cobalt (Co), Nickel (Ni), Copper (Cu), Zinc (Zn), Zirconium (Zr), Niobium (Nb), Molybdenum (Mo), Technetium (Tc), Ruthenium (Ru), Rhodium (Rh), Palladium (Pd), Silver (Ag), Cadmium (Cd), Hafnium (Hf), Tantalum (Ta), Tungsten (W), Rhenium (Re), Osmium (Os), Iridium (Ir), Platinum (Pt), Gold (Au), Mercury (Hg), Rutherfordium (Rf), Dubnium (Db), Seaborgium (Sg), Bohrium (Bh), Hassium (Hs).

Same column (group 3): Scandium (Sc), Lanthanum (La), Actinium (Ac).