Limits RegistryPUBLIC RECORD
Limits RegistryWurtzite boron nitride and lonsdaleite (hexagonal diamond) have both been theoretically and, in some shock-compression experiments, reported to exceed cubic diamond's hardness — with nanotwinned cubic boron nitride synthesized in 2013 reaching a measured Vickers hardness of about 108 GPa, surpassing many forms of diamond and standing as the hardest bulk material directly measured after diamond itself.
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Wurtzite boron nitride and lonsdaleite (hexagonal diamond) have both been theoretically and, in some shock-compression experiments, reported to exceed cubic diamond's hardness — with nanotwinned cubic boron nitride synthesized in 2013 reaching a measured Vickers hardness of about 108 GPa, surpassing many forms of diamond and standing as the hardest bulk material directly measured after diamond itself.
The highest Vickers hardness confirmed for a synthesized superhard material other than diamond or diamond composites, whose hardness is well established separately.
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1 accepted Claim, with 1 linked evidence records.
Permanent ID limitsregistry.com/limits/LR-HARDEST-KNOWN-SUPERHARD-MATERIAL
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Limits Registry. LR-HARDEST-KNOWN-SUPERHARD-MATERIAL. Hardest known synthesized material (excluding diamond). 2026.