Zirconium
Zirconium is a strong, corrosion-resistant transition metal that's often confused with the gemstone zircon and the diamond simulant cubic zirconia, even though the pure metal itself is put to very different, highly technical uses.
- Group · Period
- 4 · 5
- At room temp
- solid
- Melts at
- 2128 K
- Density
- 6.52 g/cm³
- Discovered
- 1789
Uses
Zirconium’s most critical application is in nuclear power: alloys of the metal are used to clad the uranium fuel rods inside reactors because zirconium allows neutrons to pass through almost unimpeded, which is essential for keeping a nuclear reaction running efficiently, while also standing up to the corrosive, high-temperature water environment inside the reactor core. Its natural resistance to corrosion also makes it valuable for pumps, valves and piping that handle aggressive acids in chemical processing plants.
Zirconium oxide, or zirconia, is separately engineered into tough ceramics used in dental crowns, artificial hip and knee joints, and industrial cutting tools, while a cubic crystal form of zirconia is widely sold as a low-cost, visually convincing diamond substitute in jewelry.
History
Zirconium was first recognized in 1789 by German chemist Martin Heinrich Klaproth, who was analyzing a gemstone called zircon and found that it contained the oxide of a previously unknown element. Klaproth named the new element after the mineral itself, though he wasn’t able to isolate it in metallic form. That achievement came decades later, in 1824, when Swedish chemist Jöns Jacob Berzelius produced impure zirconium metal by heating a zirconium compound with potassium. Truly pure zirconium metal, free of the brittleness caused by trace impurities, wouldn’t be produced until industrial refining methods improved in the 20th century.
Fun facts
- Zirconium alloys are used to clad nuclear fuel rods because the metal is nearly transparent to the neutrons that keep a nuclear reaction going.
- Cubic zirconia, the popular diamond substitute, is made from zirconium oxide and is a different material entirely from the natural mineral zircon.
- Zirconium resists corrosion so well that it's used to build equipment that handles highly corrosive acids in chemical plants.
Frequently asked questions
What's the difference between zirconium, zircon and cubic zirconia?
Zirconium is the metallic element itself. Zircon is a naturally occurring gemstone mineral — zirconium silicate — that the element was originally discovered in and takes its name from. Cubic zirconia is a lab-made crystal of zirconium oxide, prized as an affordable diamond simulant, and is chemically unrelated to natural zircon beyond sharing the same metal.
Why is zirconium important in nuclear power plants?
Zirconium alloys are used to encase, or clad, the uranium fuel pellets inside a reactor because zirconium barely absorbs the neutrons needed to sustain the nuclear reaction, unlike most other metals. It's also strong and highly resistant to corrosion in the hot, high-pressure water environment inside a reactor.
When was zirconium discovered versus first isolated as a pure metal?
German chemist Martin Heinrich Klaproth identified zirconium oxide as a new substance in 1789 while analyzing the mineral zircon, but it took until 1824 for Jöns Jacob Berzelius to isolate the metal itself in a usable, if impure, form.
Compounds
5 notable compounds containing Zr
- ZrCindustrial
Zirconium carbide
An extremely hard, refractory ceramic with one of the highest melting points known among simple compounds, giving it excellent resistance to extreme heat.
Used for: Ultra-high-temperature ceramic coatings for aerospace and cutting tools
- ZrO2oxide
Zirconium dioxide (zirconia)
A hard, chemically inert white oxide that, when stabilized with yttria, becomes extremely tough and is cut as a diamond-simulant gemstone (cubic zirconia).
Used for: Cubic zirconia gemstones, dental crowns, and thermal barrier coatings
- ZrNindustrial
Zirconium nitride
A hard, gold-colored ceramic coating material valued for its wear resistance and metallic luster, which makes it a popular substitute for gold plating.
Used for: Decorative and wear-resistant coating on tools and watch cases
- ZrSiO4mineral
Zirconium silicate (zircon)
A hard, durable mineral that is the main natural ore of zirconium and one of the oldest minerals found on Earth, prized for its brilliance when cut as a gemstone.
Used for: Gemstone, ceramic glaze opacifier, and primary ore of zirconium
- ZrCl4halide
Zirconium tetrachloride
A white, moisture-sensitive solid that fumes in air and serves as the key intermediate in refining zirconium metal from its ores.
Used for: Intermediate in zirconium metal purification and a catalyst component
Isotopes
38 known isotopes
Swipe to see all columns →
| Isotope | Natural abundance | Half-life | Decay mode | Mass excess | Binding energy / nucleon | Decay width |
|---|---|---|---|---|---|---|
| Zr-90 stable | 51.45% | Stable | — | -88,772.55 keV | 8,709.97 keV | — |
| Zr-91 stable | 11.22% | Stable | — | -87,895.59 keV | 8,693.31 keV | — |
| Zr-92 stable | 17.15% | Stable | — | -88,459.02 keV | 8,692.68 keV | — |
| Zr-94 stable | 17.38% | Stable | — | -87,269.33 keV | 8,666.8 keV | — |
| Zr-96 | 2.8% | 2.0E+19 Y | Unknown | -85,438.86 keV | 8,635.33 keV | 7.23 × 10-43 eV |
Show all 38 isotopes
| Zr-77 | — | — | Electron capture / beta-plus decay, ECP, Two-proton emission | -31,600 keV | 8,075 keV | — |
| Zr-78 | — | 170 ns | Electron capture / beta-plus decay | -40,850 keV | 8,194 keV | 2.68 × 10-9 eV |
| Zr-79 | — | 56 ms | Electron capture / beta-plus decay (100%), ECP | -46,770 keV | 8,267 keV | 8.15 × 10-15 eV |
| Zr-80 | — | 4.6 s | Electron capture / beta-plus decay (100%), ECP | -54,760 keV | 8,365 keV | 9.92 × 10-17 eV |
| Zr-81 | — | 5.5 s | Electron capture / beta-plus decay (100%), ECP (0.12%) | -57,524.42 keV | 8,395.15 keV | 8.30 × 10-17 eV |
| Zr-82 | — | 32 s | Electron capture / beta-plus decay (100%) | -63,614.06 keV | 8,465.47 keV | 1.43 × 10-17 eV |
| Zr-83 | — | 42 s | Electron capture / beta-plus decay (100%), ECP | -65,911.66 keV | 8,488.4 keV | 1.09 × 10-17 eV |
| Zr-84 | — | 25.8 m | Electron capture / beta-plus decay (100%) | -71,421.69 keV | 8,549.03 keV | 2.95 × 10-19 eV |
| Zr-85 | — | 7.86 m | Electron capture / beta-plus decay (100%) | -73,175.2 keV | 8,564.04 keV | 9.67 × 10-19 eV |
| Zr-86 | — | 16.5 h | Electron capture / beta-plus decay (100%) | -77,969.02 keV | 8,614.05 keV | 7.68 × 10-21 eV |
| Zr-87 | — | 1.68 h | Electron capture / beta-plus decay (100%) | -79,347.15 keV | 8,623.65 keV | 7.54 × 10-20 eV |
| Zr-88 | — | 83.4 d | Electron capture (100%) | -83,628.87 keV | 8,666.03 keV | 6.33 × 10-23 eV |
| Zr-89 | — | 78.41 h | Electron capture / beta-plus decay (100%) | -84,877.97 keV | 8,673.39 keV | 1.62 × 10-21 eV |
| Zr-93 | — | 1.61E+6 Y | Beta-minus decay (100%) | -87,122.03 keV | 8,671.62 keV | 8.98 × 10-30 eV |
| Zr-95 | — | 64.032 d | Beta-minus decay (100%) | -85,659.94 keV | 8,643.59 keV | 8.25 × 10-23 eV |
| Zr-97 | — | 16.749 h | Beta-minus decay (100%) | -82,936.69 keV | 8,603.72 keV | 7.57 × 10-21 eV |
| Zr-98 | — | 30.7 s | Beta-minus decay (100%) | -81,281.76 keV | 8,581.4 keV | 1.49 × 10-17 eV |
| Zr-99 | — | 2.1 s | Beta-minus decay (100%) | -77,616.67 keV | 8,539.23 keV | 2.17 × 10-16 eV |
| Zr-100 | — | 7.1 s | Beta-minus decay (100%) | -76,372.74 keV | 8,522.11 keV | 6.43 × 10-17 eV |
| Zr-101 | — | 2.3 s | Beta-minus decay (100%) | -73,160.99 keV | 8,485.84 keV | 1.98 × 10-16 eV |
| Zr-102 | — | 2.9 s | Beta-minus decay (100%) | -71,581.43 keV | 8,466.29 keV | 1.57 × 10-16 eV |
| Zr-103 | — | 1.3 s | Beta-minus decay (100%) | -67,808.99 keV | 8,425.83 keV | 3.51 × 10-16 eV |
| Zr-104 | — | 1.2 s | Beta-minus decay (100%) | -65,717.66 keV | 8,402.32 keV | 3.80 × 10-16 eV |
| Zr-105 | — | 0.66 s | Beta-minus decay (100%), Beta-minus, neutron emission (2%) | -61,458.27 keV | 8,358.6 keV | 6.91 × 10-16 eV |
| Zr-106 | — | 180 ms | Beta-minus decay (100%), Beta-minus, neutron emission (7%) | -58,749 keV | 8,330 keV | 2.53 × 10-15 eV |
| Zr-107 | — | 146 ms | Beta-minus decay (100%), Beta-minus, neutron emission (23%) | -54,020 keV | 8,284 keV | 3.12 × 10-15 eV |
| Zr-108 | — | 77.4 ms | Beta-minus decay (100%), Beta-minus, neutron emission | -50,950 keV | 8,253 keV | 5.89 × 10-15 eV |
| Zr-109 | — | 56 ms | Beta-minus decay (100%) | -45,730 keV | 8,204 keV | 8.15 × 10-15 eV |
| Zr-110 | — | 37.5 ms | Beta-minus decay (100%), B-2N, Beta-minus, neutron emission | -42,220 keV | 8,171 keV | 1.22 × 10-14 eV |
| Zr-111 | — | 24.0 ms | Beta-minus decay (100%), B-2N, Beta-minus, neutron emission | -36,480 keV | 8,118 keV | 1.90 × 10-14 eV |
| Zr-112 | — | 30 ms | Beta-minus decay (100%), B-2N, Beta-minus, neutron emission | -32,420 keV | 8,081 keV | 1.52 × 10-14 eV |
| Zr-113 | — | — | Beta-minus decay (100%), Beta-minus, neutron emission, B-2N | -26,340 keV | 8,027 keV | — |
| Zr-114 | — | — | Beta-minus decay (100%), Beta-minus, neutron emission, B-2N | — | — | — |