Praseodymium is the chemical element with symbol Pr and atomic number 59. It is a soft, silvery lanthanide metal that tarnishes in air and is normally found mixed with other rare-earth elements.
Praseodymium quick facts
| Property | Value |
| Symbol | Pr |
| Atomic number | 59 |
| Relative atomic mass | 140.908 |
| Period | 6 |
| Block | f-block |
| Density | 6.77 g/cm³ |
| Melting point | 931°C |
| Boiling point | 3520°C |
| Electron configuration | [Xe] 4f³ 6s² |
| Common oxidation state | +3 |
| CAS number | 7440-10-0 |
| Stable natural isotope | ¹⁴¹Pr |
Chemistry and occurrence
Praseodymium chemistry is dominated by Pr³⁺, although higher oxidation states occur in some oxides. It is separated from minerals such as monazite and bastnäsite using solvent extraction and ion exchange.
See the complete CleverlySmart periodic table.
Important uses
- Permanent magnets: praseodymium can partly replace neodymium in high-performance rare-earth magnets.
- Aircraft alloys: praseodymium-magnesium alloys combine light weight and useful strength.
- Glass and ceramics: praseodymium compounds produce clear yellow-green colours in glass, enamel and glazes.
- Didymium glass: praseodymium and neodymium help filter intense yellow and infrared radiation in glass-working goggles.
- Lighting and catalysts: compounds are used in specialised lamps and chemical catalysts.
Praseodymium isotopes
Natural praseodymium consists entirely of stable ¹⁴¹Pr. Radioactive isotopes such as ¹⁴²Pr and ¹⁴³Pr are produced artificially. See the CleverlySmart isotope table for broader data.
Biological role and safety
Praseodymium has no known biological role. It is generally considered to have relatively low toxicity, but dusts, powders and soluble compounds still require normal chemical safety controls.
Discovery and name
In 1885, Carl Auer von Welsbach separated the material called didymium into praseodymium and neodymium. The name comes from Greek words meaning green twin, reflecting the colour of many praseodymium salts and its close association with neodymium.



