Lawrencium - Lr
Lawrencium (Lr)
Lawrencium is a radioactive actinide produced in very small quantities. It does not have a standard atomic weight; the bracketed value below identifies a representative isotope mass number.
| Atomic number | 103 |
|---|---|
| Representative isotope mass number | [262] |
| Electron configuration | [Rn] 5f14 7s2 7p1 |
| Density | not established |
| Melting point | 1627 (estimated) °C |
| Boiling point | not established |

Uses and applications
Lawrencium has no applications outside research. Only a few atoms have been produced, mainly to investigate the properties and periodic-table position of the heaviest actinide.
Lawrencium and water management
Lawrencium is not used in water treatment and is not expected in ordinary water supplies. Any possible occurrence in research or nuclear waste would require specialised radiological characterisation and management.
Occurrence and environmental context
Lawrencium is a synthetic actinide with no stable isotopes. Its occurrence outside controlled production is extremely limited. Environmental assessment, if relevant, depends on isotope, activity, chemical form, and the specific source.
Health and safety
Lawrencium requires specialised radiological controls. Exposure risk depends on isotope, activity, chemical form, and exposure route. Follow applicable radiation-protection procedures and institutional requirements when handling radioactive materials or waste.
Back to the periodic table of elements
Sources and further reading
Element page last reviewed: 24 October 2026 by Lenntech.