According to gizmag.com report, Physical Review Letters will soon publish the findings of a research team, about the discovery of a new, fourth Carbon Allotrope, added to the other already known three allotropes (diamond, graphite and graphene).
The new diamond-like allotrope is in fact harder and tougher than diamond, because it's atomic-level structure; "Unlike crystalline forms of carbon such as diamonds, whose hardness is highly dependent upon the direction in which the crystal is formed, the new form of carbon is amorphous meaning it could be equally strong in all directions"