| S.No. | The Hardest In World | Description |
| 1 | The hardest known natural material |
Diamond
|
| 2 | The hardest, densest substance in the DC universe | Inertron |
| 3 | The hardest piece of equipment in the water care system |
spa filters
|
| 4 | The hardest shot in ice hockey |
Slapshot
|
| 5 | The hardest mountain-ultramarathon in the Canary Islands | Transvulcania is a long distance race |
| 6 | The hardest shot in ice hockey | slapshot |
| 7 | The hardest and most highly mineralized substance in the human body |
Tooth enamel
|
| 8 | The town framed for manufacturing hardest and densest building bricks | Accrington towns , Lancashire |
| 9 | The hardest known oxide | Stishovite |
| 10 | The hardest of all wheats | Durum wheat |
