Limits RegistryPUBLIC RECORD
Limits RegistryLithium has a density of just 0.534 g/cm³ — about half that of water — making it the least dense metal, and light enough that it floats on water (while also reacting vigorously with it).
The question, scope, and sources behind this Registry record.
Lithium has a density of just 0.534 g/cm³ — about half that of water — making it the least dense metal, and light enough that it floats on water (while also reacting vigorously with it).
The lowest density of any metallic element, measured at standard conditions.
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Current frontiers derived from accepted Claims.
An observed or demonstrated result; no opposing bound is implied.
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The frontier as it changed over time.
Only accepted Claims matching the current specification contribute to the displayed bounds. Strict inequalities remain open; contradictory Claims require editorial review.
Permanent ID limitsregistry.com/limits/LR-LEAST-DENSE-METAL
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Limits Registry. LR-LEAST-DENSE-METAL. Least dense metal. 2026.