Diamond is often considered one of the hardest naturally occurring materials in the world. However, a synthetic material called aggregated diamond nanorods has been found to be even harder, making it one of the hardest solids known to date.
Diamond is the hardest materail in the world
The name of the hardest solid is a diamond; it is the hardest object known to humankind.
A diamond
Diamond is already a solid: it is the hardest mineral known.
Earth would have to be the hardest of the Aristotelean Elements as it is the only solid one.
diamond is the strongest solid; almost impossible to break (:
Diamond is the hardest substance in the world
yes.
c b s e is the hardest course in the world
30 on the WORLD'S HARDEST GAME on AddictingGames
No, diamond is the hardest known natural substance in the world.